Chapter 8 Source of Useful Traits

Leonard W. Panella, Piergiorgio Stevanato, Ourania Pavli and George Skaracis

Abstract In the late 1800s, there already was speculation that maritima might provide a reservoir of resistance genes that could be utilized in breeding. European researchers had crossed Beta maritima and sugar beet and observed many traits in the hybrid progeny. It is impossible to estimate how widely Beta maritima was used in the production of commercial varieties, because most of the germplasm exchanges were informal and are difficult to document. Often these crosses of sugar beet with sea beet germplasm contained undesirable traits, e.g., annualism, elongated crowns, fangy roots, high fiber, red pigment (in root, leaf, or petiole) and much lower sucrose production. It is believed that lack of acceptance of Beta maritima as a reservoir of genes was because most of the evaluations of the progeny were done in early generations: The reactions of the hybrids vulgaris × maritima were not impressive, and it is clear now that they were not adequately studied in the later generations.

Keywords Disease resistance · Rhizomania · · · Drought · Salt stress · Root rot · Curly top · Virus yellows · Powdery mildew · Polymyxa betae

Contrary to other species of the genus Beta, the evolutionary proximity between the sea beet and the cultivated types favors casual crosses (Hjerdin et al. 1994). Important characters of resistance to diseases, currently present in cultivated varieties, have been isolated from wild material (Table 8.1). According to several authors, Beta maritima is also an important means to increase the genetic diversity of cultivated types, now rather narrow from a domestication bottleneck and continuous selection for improve- ment of production and quality traits (Bosemark 1979; de Bock 1986; Doney 1998;

L. W. Panella (B) Colorado State University, 3944 Century Dr., Fort Collins, CO 80526, USA e-mail: [email protected] P. Stevanato DAFNAE, University of Padua, Padova, Italy O. Pavli · G. Skaracis Agricultural University of Athens, Athina, Greece This is a U.S. government work and not under copyright protection 167 in the U.S.; foreign copyright protection may apply 2020 E. Biancardi et al. (eds.), Beta maritima, https://doi.org/10.1007/978-3-030-28748-1_8 168 L. W. Panella et al.

Table 8.1 Useful traits in the Genus Beta (Frese 2011, personal communication) Beta and Taxa TRAIT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Annual life cycle Monogermity Hard seedeness Seed shattering CMS Genetic male sterility Salt tolerance Frost tolerance Curly Top Yellowing viruses BYV Beet mild yellowing virus BMYV Beet mosaic virus BMV Beet necrotic yellow vein virus BNYVV Yellow wilt Peronospora farinosa betae Rhizoctonia solani Cercospora beticola Polymyxa betae Black leg disease Erwinia subsp. schachtii Heterodera trifolii Meloidogyne hapla Meloidogyne incognita Meloidogyne javanica Meloidogyne arenaria Myzus persicae Pegomya spp.

1. subsp. vulgaris (Bv), 2. Bv leaf beet group, 3. Bv garden beet group, 4. Bv fodder beet, group, 5. Bv sugar beet group, 6. Beta vulgaris subsp. maritima,7.Bv subsp. adanensis, 8. Beta (Beta) macrocarpa,9.Beta patulaI, 10. Beta corolliflora, 11. Beta macrorhiza, 12. Beta lomatogona, 13. Beta intermedia, 14. Beta trigyna, 15. Beta nana, 16. Patellifolia (Patellifolia ) procumbens, 17. Patellifolia webbiana, 18. Patellifolia patellaris 8 Source of Useful Traits 169

Jung et al. 1993; McGrath et al. 1999). This is especially true of sugar beet varieties, due to the common origin from the White Silesian Beet (Achard 1803; Fischer 1989), whose variability, according to Evans and Weir (1981), could have been enhanced by crosses with North Atlantic sea beet. Moreover, this narrowing of genetic diversity was increased through the widespread use both of Owen’s cytoplasmic genetic male sterility (CMS) and the monogermy trait transferred to the current varieties by means of inbred lines (Jung et al. 1993; Owen 1945; Savitsky 1952). The attempts to trans- fer useful traits from sea beet are still underway. In a recent paper, Campbell (2010) described the performance of four crosses between Beta maritima and commercial varieties, which performed quite well, both in yield and resistance to some diseases (Rhizoctonia root and crown rot, rhizomania, powdery mildew, Cercospora leaf spot, Aphanomyces root rot, and Fusarium yellows). However, the association of negative characters with the traits to be transferred often has made the improvement of cultivated genotypes difficult (Coons 1975; Mita et al. 1991). The major problems associated with such hybridizations are (1) the dominance of the annual life cycle in some wild forms, (2) the very bad shape of the root, (3) woodiness of roots, (4) elongated and multiple crowns, (5) low sugar content, (6) poor root yield, (7) low processing quality (Oltmann et al. 1984), (8) growth habit of the seed stalk, (9) prostrate seed stalk, (10) early seed shattering, etc. (Rasmussen 1932; van Geyt et al. 1990). Similar problems also arise when crossing sea beet with fodder, leaf, and garden beets. Several backcrosses and repeated selection cycles are necessary before such hybrids can acquire a satisfactory morphology and sufficient agronomic qualities (de Bock 1986; Munerati 1932). The ancestors of the modern crops are defined as “crop wild relatives” (CWR), which also include other species closely related to them (Hajjar and Hodgkin 2007). Their commercial worth is invaluable (www.biodiversityinterna-tional.org). Many wild species, including Beta maritima, are threatened through reduction, degradation, or fragmentation of their habitat. Therefore, we need to identify not only the species to be protected in their respective areas but also the facilities for their in situ and ex situ conservation (Frese and Germeier 2009). Maxted et al. (2006) subdivided the species of the genus Beta into gene pools (GP) (Harlan and de Wet 1971) according to the difficulty of using the pool as a source of traits for the beet crops: (1) primary gene pool includes the cultivated forms (GP-1A) and the wild or weedy forms of the crop (GP-1B); (2) secondary gene pool (GP-2) includes the less closely related species from which gene transfer to the crop is difficult, but possible, using conventional breeding techniques; and (3) tertiary gene pool (GP-3) includes the species from which gene transfer to the crop is impossible or requires sophisticated techniques. Consequently, Beta maritima was classified as explained in Table 6.2. A PGR Forum was organized both to better define CWR and to compile a list of the more endangered species (Ford-Lloyd et al. 2009). 170 L. W. Panella et al.

8.1 Resistances to Biotic Stresses

Most of the breeding work with Beta maritima has been to use it as a source of resistance to varied pests and diseases. Lewellen (1992) theorized that because the sugar beet and the white Silesian fodder beet source were developed and produced in the temperate climate of Northern Europe, there was less pressure to maintain resistance to biotic stress because of the mild disease incidence and “As a consequence, this narrowly based germplasm may never have had or may have lost significant levels of genetic variability for disease resistance or the factors that condi- tion disease resistance occur in the germplasm at low frequencies” (Lewellen 1992). However, once sugar beet production moved out of Northern Europe, east into Russia and Asia, south into Mediterranean Europe and North Africa, and west into England and North and South America, many new diseases endemic to these areas limited production of sugar beet (Lewellen 1992). The first documented instance of successfully transferring disease resistance from sea beet to sugar beet was by Munerati using sea beet growing in the Po Delta as a source of resistance to Cercospora leaf spot (Munerati et al. 1913a). Following Munerati’s success, other European researchers began working with Beta maritima as a source of disease resistance (Margara and Touvin 1955; Schlösser 1957; Zossi- movich 1939; Asher et al. 2001a). Nonetheless, for many of the reasons enumerated by Coons (1975), it is unlikely that much of this effort resulted in commercial vari- eties with sea beet in their genetic background, and due to the proprietary status of commercial germplasm, this information has not found its way into the literature.

8.1.1 Yellowing Viruses

Virus yellows (VY) is an important disease of sugar beet (Fig. 8.1). It is most severe and persistent in mild maritime climates such as Pacific coastal states of the USA, Western Europe, and Chile. These climates provide a long season for sugar beet for both root and seed crops, give a potentially continuous reservoir of virus–host sources, and favor the overwinter survival of the aphid species that transmit the viruses. VY is caused by the closterovirus Beet yellows virus (BYV), and the poleroviruses Beet western yellows virus (BWYV), Beet chlorosis virus (BChV) (Duffus and Liu 1991; Liu et al. 1999), and Beet mild yellows virus (BMYV). The principal aphid vector is the green peach aphid (Myzus persicae Sulzer) (Watson 1940) but many other species are known to vector one or more of these viruses. BMYV, BChV, and BYV can decrease sugar yield by at least 30%, 24%, and 49%, respectively (Smith and Hallsworth 1990; Stevens et al. 2004). Breeding for resistance in sugar beet started in Europe in 1948 and in 1957 in the USA (Bennett 1960; de Biaggi 2005;Duffus1973; Duffus and Ruppel 1993; Hauser et al. 2000; Luterbacher et al. 2004; McFarlane and Bennett 1963; Rietberg and Hijner 1956; Stevens et al. 2004, 2005, 2006). 8 Source of Useful Traits 171

Fig. 8.1 Vein of beet yellows virus on sugar beet

Likely, the agents that cause VY have coevolved with Beta spp. It would seem then that a desirable place to search for high host–plant resistance to one or more of the viruses would be in the primary and secondary germplasms (Luterbacher et al. 2004; Panella and Lewellen 2007). Conventional breeding for resistance to VY has been moderately successful within sugar beet, but most sources of resistance are quantitatively inherited and have low heritabilities. This makes transfer from exotic sources to elite breeding lines and parents of hybrids very difficult. Other than the cultivated beet crops, Beta maritima would be the most logical place to find the desired genetic variability. However, little known research has been done within Beta maritima for VY resistance. Grimmer et al. (2008a) reported that resistance to BMYV was identified in wild accessions and successfully transferred to early generation backcrosses with sugar beet. Luterbacher et al. (2004) assessed resistance to BYV in 597 Beta accessions collected worldwide and identified highly resistant individual accessions. Resistant individual were crossed with sugar beet plants to generate populations for mapping (Francis and Luterbacher 2003). The results from mapping these popula- tions were reported by Grimmer et al. (2008b). Using AFLP and SNP markers, a locus controlling vein-clearing (Fig. 8.2) or mottling symptoms caused by incipi- ent BYV infection was mapped to chromosome IV and given the name Vc1. Three BYV resistance QTLs were identified and mapped to chromosomes III, V, and VI. QTLs on chromosomes III and V acted only in plants showing mottled symptoms. Vein-clearing symptoms were controlled only in plants with allele Vc1 on Chromo- some VI. These results and concurrently run ELISA tests for BYV suggest that BYV resistance breeding can be facilitated by employing molecular marker techniques (Grimmer et al. 2008b) but the inheritance of resistance is still rather complex with unknown outcomes in the field. Breeding for VY resistance at Salinas, CA had been one of the long-term objectives of the sugar beet breeding program starting in 1957 for BYV (McFarlane and Bennett 172 L. W. Panella et al.

Fig. 8.2 Virus yellows inoculated trials at Salinas

1963), then changing to BWYV (Lewellen and Skoyen 1984), and then to BChV (Lewellen et al. 1999). Despite preliminary tests with wild beet species that suggested “It seems unlikely that any of the wild species tested will be of value in the program of breeding for resistance to beet yellows” (McFarlane and Bennett 1963), it seemed important to determine if higher, more heritable resistance could be found in Beta maritima. Several lines with resistance have been released from this later work, including C927-4 (Lewellen 2004d). The development and traits of line R22 also called C50 and C51 (Lewellen 2000b) are discussed in Sects. 8.1.3 and 8.1.11.1. Other populations, for example, C26 and C27, containing Beta maritima germplasm also were developed (Lewellen 2000b). One of the objectives in breeding R22, C26, and C27 was to find higher resistance to VY from Beta maritima. Advanced cycle synthetics of R22 were further backcrossed into sugar beet and reselected for VY resistance (Lewellen 2004c). Spaced plants grown in the field were inoculated with BYV, BWYV, and/or BChV and selected on the basis of individual sugar yield and freedom from yellowing symptoms. Trials in the UK with BChV were run to show that BChV caused significant losses (Stevens and Hallsworth 2003). At Salinas, compared to susceptible, unselected sugar beet, germplasm lines with Beta maritima had reduced losses to BChV (Table 8.2). However, in developing R22 and its backcrosses, moderately VY-resistant/tolerant sugar beet parents were used that showed similar responses to VY. It is unclear if any additional genetic variation for resistance was introduced from the Beta maritima sources. These tests did suggest, however, that mass selection for VY resistance based on components of sugar yield lead to higher sugar yield and percentage sugar performance than what might be expected for lines with up to 50% of their germplasm from Beta maritima. 8 Source of Useful Traits 173

Table 8.2 One component of virus yellows is Beet chlorosis virus (BChV). Comparison of breeding lines under BChV inoculated and non-inoculated conditions at Salinas, CA, including lines with germplasm from Beta maritima Variety References Description BChV Inoculated %Loss2 Yellows 3 SY1 (kg/ha) %Sugar score Susceptible checks SP6322-0 Coe and Selected 9860 14.3 36 6.9 Hogaboam without (1971) exposure to VY4 US 75 McFarlane Selected 11,100 13.1 28 5.2 and Price from US 22 (1952) Virus yellows selected starting 1957 C37 Lewellen VY selected 17,200 16.1 7 2.7 et al. (1985) from US 75 C31/6 Lewellen VY selected 16,200 15.4 7 2.9 (PI 590799) from US × European VY selections C76-89-5 Lewellen Full-sib 17,900 16.3 1 2.0 (1998) family from C31/6 C69/2 Lewellen VY selected 19,000 17.0 6 3.5 (2004a, b, composite c, d) of all VY selections Lines with Germplasm from Beta maritima C67/2 Lewellen 10% Beta 18,000 16.5 6 3.5 (2004a, b, maritima c, d) through R22 (C51) C26 × C27 Lewellen 50% Beta 17,000 16.2 2 3.1 (2000b) maritima C37 × Atlantic Beta maritima

LSD(0.05) 1700 0.9 0.4 1SY is gross sugar yield (root yield × % sugar). Field trial area fumigated with methyl bromide in 2000 to reduce the effects of soilborne diseases and pests 2Relative % loss due to BChV calculated from variety means from adjacent companion tests planted on February 27, 2002, BChV inoculated on May 9, 2002, and harvested on October 15, 2002 3Virus yellows foliar symptoms scored every 3 weeks during chronic infection from late June to mid-August on a scale of 1–9, where 9 = 100% yellowed canopy. r = 0.81** for % loss × VY scores 4VY = BYV, BWYV, and BChV in the USA 174 L. W. Panella et al.

8.1.2 Beet Mosaic Virus

Infection by Beet mosaic virus (BtMV) is one of the most common diseases of sugar beet and other cultivated beets (Lewellen and Biancardi 2005). In California, it is almost always found in weed and wild beets of various origins growing near the Pacific coast in a perennial manner. The virus is transmitted nonpersistently by aphids including the green peach aphid (Myzus persicae Sulzer), often in association with VYs and is easily mechanically transmitted (Dusi and Peters 1999). It is common where cultivated beet is grown as a winter crop or overwintered for seed production (Shepherd et al. 1964). The damage caused by BtMV is small compared to that caused by VYs (Shepherd et al. 1964). Because damage from most BtMV infections is modest, it has received low priority or no interest from breeders and seed companies. Major gene resistance was not known in sugar beet. However, in a self-fertile (Sf ), annual (BB) line of sugar beet developed by Owen (1942) from Munerati germplasm (Abegg 1936), Lewellen (1973) identified an incompletely dominant gene that conditions resistance. He named this gene Bm. In both classical linkage and molecular marker research, this gene was found to be linked to the locus for genetic male sterility (A1) on Chro- mosome1(Friesenetal.2006). The Bm allele was also backcrossed into biennial (bb) sugar beet backgrounds and evaluated under artificially inoculated conditions in replicated field trials (Lewellen et al. 1982). When all plants were inoculated in the four- to six-leaf stage, BmBm/Bmbm plants expressed high resistance, whereas the susceptible bmbm recurrent parents showed sugar yield losses that ranged from 8 to 22%. In singly and dually inoculated treatments with components of VYs, the damage caused by BtMV was additive as previously shown by Shepherd et al. (1964). BtMV-resistant breeding lines were released as C32 (PI 590675), C43 (PI 590680), and C719 (PI 590761) (Lewellen et al. 1982). The Bm factor for resistance to BtMV was not found in Beta maritima directly, but in a sugar beet annual that likely had a Beta maritima source from Munerati’s annual (Owen 1942). This suggests that even when not done intentionally, over time useful genes and traits from Beta maritima have probably enriched sugar beet germplasm.

8.1.3 Rhizomania

Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is one of the most destructive diseases of sugar beet (Biancardi et al. 2002; Tamada and Baba 1973). BNYVV is transmitted by the obligate root parasite Polymyxa betae Keskin (Fujisawa 1976). Rhizomania was initially found in Italy (Fig. 8.3), then Japan, and it gradually spread over most sugar beet-growing areas worldwide (Biancardi et al. 2002; Brunt and Richards 1989; Scholten and Lange 2000). Polymyxa betae is distributed more widely than the BNYVV (Brunt and Richards 1989). Rhizomania is a disease, but its control is well reviewed by Biancardi and Tamada (2016). 8 Source of Useful Traits 175

Fig. 8.3 Roots severely diseased by rhizomania (above) and by cyst nematodes (below). (Donà dalle Rose 1951)

The first assessments of commercial varieties in rhizomania-infested fields began in 1958 (Bongiovanni 1964), i.e., before the discovery of the disease’s causal agent, attributed to Canova (1966).1 Results from early field tests (Fig. 8.4), along with data from trials of seed companies from 1966 onward (Gentili and Poggi 1986), showed clearly that Alba P and some other similar multigerm diploid varieties of Italian

1Canova used the Italian term “rizomania” for the disease, which had been introduced around 50 years earlier by Munerati (Munerati and Zapparoli 1915). According to Biancardi et al. (2010), this term and not “rhizomania” should be employed for the disease. 176 L. W. Panella et al.

Fig. 8.4 Susceptible variety sown between “Alba”-resistant multigerm families (San Pietro in Casale, Italy, 1979)

origin were the most productive varieties in rhizomania-infested soils (Biancardi et al. 2002). The varieties in question also possessed good Cercospora Leaf Spot (CLS) resis- tance as a consequence of their parentage from Munerati’s genotypes, from which the CLS resistance was obtained (Sect. 8.1.7). It is likely that these old genotypes also provided the genes conditioning the quantitative resistance to rhizomania car- ried by the variety Alba P (Biancardi et al. 2002; Lewellen and Biancardi 1990). It has been ascertained that the resistance of “Alba type” is governed by genes with additive effects (Biancardi et al. 2002; Frese 2010; Lewellen and Biancardi 1990). In the period from 1980 to 1985, the variety Rizor was bred at the SES-Italy breeding station, carrying a gene for qualitative rhizomania resistance (Fig. 8.5). The variety was much more productive than the varieties with quantitative resistance cultivated at the time (de Biaggi 1987). Additional information regarding the Alba and Rizor resistances is given in step 11, Sect. 1.7. In 1983, rhizomania was first found in North America in a field located in Cal- ifornia on the USDA-ARS station, Salinas, CA by R. T. Lewellen and confirmed 8 Source of Useful Traits 177 to be BNYVV (Duffus et al. 1984). Individual beets, exhibiting symptoms of both necrotic yellow veins and root bearding, were found in a field where beet cyst nema- tode (Heterodera schachtii Schmidt) trials had been conducted. In order to enrich the inoculum, soil had been incorporated from several commercial sugar beet fields reported to be infested with beet cyst nematode (McFarlane et al. 1982). It may be that the root damage on nematode-resistant genotypes, owing to the Patel- lifolia procumbens resistance, was not due to sensitivity to cyst nematode infection, as reported by McFarlane et al. (1982), but instead was due to BNYVV. Following the initial reports on rhizomania to the sugar beet industry in 1983, suspicious fields were further reported in several locations. One of these was the variety trial field of Holly Sugar’s breeding program at Tracy, CA, where severe damage was observed by Erichsen on all entries except for one series of experimental three-way hybrids. The researchers at Salinas were asked by Erichsen to visit the trial (Fig. 8.6). It was determined that BNYVV rather than cyst nematode likely caused this differential reaction (Biancardi et al. 2002) (Fig. 8.7). Plants from Holly experimental hybrids were crossed to susceptible sugar beet, and the F1 plants were selfed. In a field test at Salinas under rhizomania condi- tions, 13-week-old individual S1 families were either homozygous susceptible or segregated approximately 3 resistant:1 susceptible, thus supporting the hypothe- sis that resistance was controlled by a single dominant gene (Lewellen et al. 1987) (Fig. 8.8). Individually and collectively, the segregating S1 families fitted the expected 3:1 (resistant:susceptible) ratio (Fig. 8.9).

Fig. 8.5 Rhizomania diseased field at Phitiviers, France, showing the resistant plot (1983) 178 L. W. Panella et al.

Fig. 8.6 Rhizomania diseased field at Tracy, CA (1983)

Fig. 8.7 Susceptible variety USH11. Non-fumigated (left) and fumigated soil

The gene for resistance, unofficially called the “Holly” gene, initially was named Rz (subsequently referred to as Rz1) (Lewellen 1988). The source of Rz1 could not be determined by pedigree and breeding records (Erichsen, personal communication, 1987), but it is thought that it likely arose from unknown or unintended outcrosses to Beta maritima, as no other similar gene could be found within cultivated beets (Biancardi et al. 2002). This gene provided high-level resistance to BNYVV. The resistance found in the commercial cultivar “Rizor” (developed by SES in Italy) (Biancardi et al. 2002; de Biaggi 1987; de Biaggi et al. 2003) and Rz1 are the only major resistance genes found in the commercial sugar beet gene pool (Biancardi et al. 2002; Scholten and Lange 2000). The origin of the quantitative resistance to 8 Source of Useful Traits 179

Fig. 8.8 S1 families under rhizomania at 10 weeks, Salinas CA, 1986

Fig. 8.9 Roots showing segregation within S1 family at 13 weeks, Salinas CA, 1986 rhizomania “type Alba” and qualitative (type “Rizor” and “Holly”) is attributable to materials derived from crosses with Beta maritima and obtained from Munerati (Biancardi et al. 2002). More recently, using molecular tools, it was confirmed that the resistance found in Rizor and the Holly material did not come from separate genetic sources (Stevanato et al. 2015). This evidence is indicative of the fact that the SES pollinator used most likely originated from the Ro 281 family (from Munerati’s work) or a similar germplasm, which had been probably bred in public and private programs and then found its way to Holly Sugar through typical exchanges of germplasm (Panella and Biancardi 2016). 180 L. W. Panella et al.

Once rhizomania was recognized in California, an extensive program to find host resistance by screening Beta genetic resources (cultivated and wild) was initiated by the USDA-ARS at Salinas. The identified resistance sources were incorporated into elite sugar beet germplasm (Biancardi et al. 2002). The Rz1 allele proved to be han- dled easily in breeding programs. Resistance breeding to rhizomania has deployed the Rz1 gene in elite germplasm worldwide (Amiri et al. 2009; Azorova and Subikova 1996; Barzen et al. 1997; Lewellen et al. 1987; Nouhi et al. 2008; Thomas et al. 1993; Whitney 1989b). However, as single dominant resistance genes often are eventually overcome by mutations in a variable pathogen gene pool, additional sources of resis- tance were sought by breeding programs worldwide. Since no additional resistant sources were found in the cultivated sugar beet gene pool, various genetic resources, especially Beta maritima accessions, were screened for rhizomania resistance (Fran- cis and Luterbacher 2003;Geyletal.1995; Panella and Lewellen 2007). The USDA-ARS germplasm improvement program used two different breeding approaches. The first breeding method focused on major gene resistance. When dis- covered, genes were backcrossed into elite sugar beet germplasm. Lewellen and coworkers identified several BNYVV-resistant Beta maritima accessions (Lewellen 1995a, 1997a), using field resistance and levels of virus titer (by ELISA) as pre- liminary evaluation assays (Whitney 1989b). A resistant accession from Denmark, WB42, was crossed with sugar beet parental line C37 (Lewellen et al. 1985) and was released as germplasm C48 and C79-3 (Lewellen 1997a; Lewellen and Whitney 1993). This resistance was shown to be different from Rz1. In growth chamber tests, it conferred higher resistance than Rz1 and was designated as Rz2 (Scholten et al. 1996, 1999). Thus far, there are five sources of resistance conditioned by a single gene from Beta maritima, although most sources have been shown to be either Rz1 or Rz2 (Biancardi et al. 2002; Panella and Lewellen 2007). Rz3, which maps to chro- mosome III, has been shown to be linked to Rz1 and Rz2 (Gidner et al. 2005). The source of Rz3 is a Beta maritima accession, WB41 (Denmark). There is a variable BNYVV-resistant expression in the heterozygote in the genetic background in which it has been evaluated. Nonetheless, sugar beets with the combination of Rz1 and Rz2 or Rz3 (in the heterozygous state) showed a lower virus titer than Rz1 alone (Gidner et al. 2005). Using R36 (Lewellen and Whitney 1993), a composite population of many Beta maritima accessions, Grimmer et al. (2007) identified a major QTL, named Rz4, that appeared to be different from Rz1, Rz2, or Rz3 and also located on chromosome III. Using a mapping population, based on C79-11 as the resistance donor, another potential resistance gene, referred to as Rz5, was identified (Grimmer et al. 2008c). The resistance in C79-11 (Lewellen and Whitney 1993) was from Beta maritima accession, WB258 (step 12, Sect. 1.7). Rz4 and Rz5 map close to Rz1 and each other, thus raising the possibility of belonging to an allelic series. In the Imperial Valley (IV) of California (near the border with Mexico) in 2003, resistant hybrids, winter beet cultivars carrying the Rz1 gene, showed rhizomania symptoms in a few fields. Over the next couple of years, laboratory, greenhouse, and field tests at Salinas confirmed that Rz1 resistance gene had been overcome (Liu et al. 2005;Rushetal.2006). Since then, resistance-breaking strains have been 8 Source of Useful Traits 181 found in major growing regions, including Colorado, Idaho, Minnesota, Nebraska, and Oregon (Liu and Lewellen 2007). Only partial resistance to these strains of BNYVV is conferred by Rz2 and Rz3 from Beta maritima, although combinations of Rz1 and Rz2 appear to condition more resistance than either alone. Encouragingly, progeny families of C79-9 (resistance from Beta maritima accession WB 151–PI 546397) appeared to have higher levels of resistance to resistance-breaking strains of BNYVV (Lewellen 1997a; Panella and Lewellen 2007). The emergence of resistance-breaking strains of BNYVV rekindled the interest in the C79 populations with multiple, different sources of rhizomania resistance backcrossed to C37, created by Lewellen at Salinas (Lewellen et al. 1985; Lewellen 1997a, b). The 11 germplasms in the C79 series were from different genetic sources of resistance to BNYVV.They had been backcrossed 1 to 6 times with C37 (Lewellen 1997a, b). The seed from these sources had been poly-crossed in the field at Salinas and, following selection, was designated as R740 and placed in storage (Panella et al. 2018). With the renewed interest in other sources of genetic resistance, this seed was sent to the USDA breeding program at Fort Collins, Colorado. SNP markers, which were linked to Rz1 and Rz2 (Stevanato et al. 2012, 2014a; Panella et al. 2015a, b), were used to select individual plants. Two germplasms were released from this project: FC1740 was selected as homozygous resistant to SNP markers linked to both Rz1 and Rz2 resistance genes (inferred genotype—Rz1Rz1Rz2Rz2), and FC1741 was selected as homozygous to the marker linked to the Rz2 gene for resistance and homozygous susceptible for rz1 (inferred genotype—rz1rz1Rz2Rz2) (Panella et al. 2018). There is a possibility that other resistance genes may also be present in these germplasms but there were no SNP markers publicly available to ascertain this at the time of their release. The second breeding method involved individual screening of Beta maritima populations and pooling the selected resistant plants—a composite approach (Doney 1993). The pooled plants were increased in mass, and there was no effort to classify the resistance sources as Rz1, Rz2, etc., or other factors. Several breeding populations were developed using this method and have been released as C26, C27, C51, R21, C67, R23, R23B, and R20 (Lewellen 2000b, 2004b). Although there are most likely major genes in these populations, the existence of additional minor resistance genes may eventually lead to a more durable resistance. In an attempt to discover novel sources of quantitative multigene resistance, Richardson et al. (2019) conducted a thorough screening of available Beta maritima germplasm collection under field and greenhouse conditions using both resistance- breaking and nonresistant-breaking strains of BNYVV. Overall findings from field and greenhouse assays pointed to the superiority of accessions from Denmark in combating BNYVV as well as resistant breaking strains of BNYVV, thus provid- ing evidence for their possible exploitation as pre-breeding donor material in future efforts aiming at the development of rhizomania-resistant varieties. Recently, the University of Padua, Italy, through a sponsored research project, has collected seeds of 35 populations of Beta maritima along the Italian and Croat- ian coasts of Adriatic Sea. Representative seed samples from each population were planted the year after collection both in the field and glasshouse. Molecular analyses 182 L. W. Panella et al. were performed in order to examine the presence of the Rz1 source of resistance. Preliminary results showed that the frequency of the Rz1 allele was significantly higher in sea beet populations collected on the Italian Adriatic coast. This would provide additional genetic proof about the speculated origin of Rz1 from the Italian sea beet gene pool (Stevanato, personal communication). In a collaborative project between the University of Padua and the USDA Fort Collins program, 24 individuals from 64 populations were screened with markers for Rz1 and Rz2. Many populations contained the Rz1 SNP marker, while there were areas where the Rz2 marker was present (unpublished data). A big future challenge is to determine the allelic diversity within these populations and to gain insight into its effect in relation to the level of resistance.

8.1.4 Beet Curly Top Virus

Curly top in beets is caused by a mixture of at least three closely related Curtoviruses in the family Geminiviridae: Beet curly top virus (BCTV), Beet mild curly top virus (BMCTV), and Beet severe curly top virus (BSCTV) (Strausbaugh et al. 2008). They are all transmitted by the beet leafhopper, Circulifer tenellus Baker (Fig. 8.10), which attacks sugar beet and many other crops cultivated in semi-arid areas (Western USA, Mexico, Turkey, and Iran) (Bennett 1971; Bennett and Tanrisever 1958; Briddon et al. 1998; Duffus and Ruppel 1993; Panella 2005b). Similar viruses occur in Argentina, Uruguay, and Bolivia (Bennett 1971). Almost as soon as the sugar beet industry was established in the Western United States, BCTV severely impacted yields (Bennett 1971; Carsner 1933; Murphy 1946). Production in California was begun in 1870, and shortly thereafter BCTV symptoms were observed on beets grown there, and by the 1920s, it was clear the sugar beet industry required varieties with resistance to BCTV to survive (Bennett 1971; Bennett and Leach 1971; Carsner 1933; Coons 1953; Murphy 1946) (Fig. 8.11). The early breeding efforts resulted in the release of US 1, a curly top-resistant open-pollinated variety that was a huge step forward (Carsner 1933). At the time of its release, researchers already were looking at Beta maritima as a potential source of resistance to BCTV (Coons et al. 1931), which probably is why Coons was commissioned in 1925 to collect Beta maritima in Europe (Coons et al. 1955). Further increases in resistance to BCTV were achieved with US 33 and US 34 selected from heavily curly top infested fields of US 1, and eventually they were superseded by US 12 and US 22, which were further improved in US 22/2 and US 22/3 (Coons et al. 1955). However, as stated by Coons et al. (1955): “Hybridizations [of Beta maritima] with sugar beets were made and the segregating generations were selected for both leaf spot resistance and curly top resistance. The outlook of obtaining resistant strains in this way was promising but not more so than from the selections made from the sugar beet itself. Since breeding work with the sugar beet did not present the problems of ridding the progenies of multicrowns and rootiness, the emphasis on wild hybrids gradually dwindled.” 8 Source of Useful Traits 183

Fig. 8.10 Leafhopper (Circulifer tenellus)

Despite what Coons states, Owen speculated that his source of extreme resistance to BCTV, which he called “strain 286”, was most likely a chance hybridization with a “wild beet” in California (Owen et al. 1939). We know that wild beets in California encompass introductions of Beta macrocarpa and Beta maritima from Europe, and may include feral domestic beets (, table beet, sugar beet) (Bartsch et al. 1999; Carsner 1928; McFarlane 1975). Owen also declared “However, some accidental hybridization of parental strains of US 1 and progenies comparable in origin with 286 is now suspected.” Certainly, the spangled roots of early 286 progeny in the 184 L. W. Panella et al.

Fig. 8.11 Beets diseased by BCTV (left) photograph in the 1946 Proceedings of the ASSBT (Owen et al. 1946) resemble progeny of sugar beet crossed with a sea beet. It is during the development of US 1 that Carsner comments on the wild beets in southern California (Carsner 1928), which lends credence to Owen’s remarks. The performance of 286 showed extreme resistance to curly top (Carsner 1926; Owen et al. 1946). CT9 and later, C569, which were widely used in the Western USA as components of curly top-resistant hybrids, were derived from this line (McFarlane et al. 1971; Owen et al. 1946). This example of Beta maritima being a largely unrecognized source of resistance and yet being characterized by Coons as difficult to work with when other sources were present in the sugar beet germplasm typifies the attitude of many of the commercial breeders who made little use of sea beet germplasm during the first 60 years of the last century (Lewellen 1992). Most of the beet curly top-resistant material in use today stems from this gene pool, which was widely used by USDA-ARS plant breeders and provided sources of strong resistance to curly top and may have been a source of resistance to other diseases. Nonetheless, there is continued screening of sea beet for resistance to all of the curly top viruses in a cooperative curly top nursery managed by the Beet Sugar Development Foundation and USDA-ARS planted in Kimberly, Idaho (Doney 1998; Hanson and Panella 2002b, 2003b, 2004a; Panella 1998b, 1999a, 2000b; Panella and Hanson 2001b; Panella and Strausbaugh 2011a, b, 2013; Strausbaugh and Panella 2014, 2015, 2016, 2017). In a recent search of the USDA-ARS National Plant Germplasm System’s (NPGS) Germplasm Resources Information Network (GRIN) Database, there are two Beta maritima accessions that 8 Source of Useful Traits 185 had better resistance than intermediate (rating of <5; 0 to 9 scale; immune to dead) to beet curly top (PI 518338 and PI 504185) (USDA-ARS 2011a).

8.1.5 Powdery Mildew

Damage from powdery mildew caused by Erysiphe polygoni DC (syn. E. betae Weltzien) is common almost everywhere sugar beet is grown. Major gene resistance has not been found in sugar beet germplasm; however, quantitatively conditioned tolerance is known and widely used in commercial varieties (Lewellen 1995b; Whit- ney et al. 1983). In an initial screen of Beta maritima accessions at Salinas in field plots in the late 1970s and early 1980s, resistance to powdery mildew was identi- fied in several accessions. In greenhouse tests on seedlings plants, Whitney (1989a) confirmed that high resistance segregated among these accessions. Two accessions (WB97 and WB242) that showed high resistance were chosen as sources of resistance in a program to determine the inheritance of resistance and transfer this resistance to sugar beet (Lewellen 2000a). WB97 (PI 546394) was in the Salinas collection assembled and evaluated by McFarlane. WB97 was sent to Salinas from the Japan Sugar Beet Improvement Foundation in 1968 and identified as Beta patula WB46 from the Wageningen collection. If WB97 (WB46) is Beta patula, then it would have been collected from dos Embarcaderos near Madeira (Lange et al. 1999). McFarlane noted that WB97 was variable and did not have typical Beta patula characteristics and was more likely Beta maritima or crosses between Beta patula and Beta vulgaris/Beta maritima. Resistance to powdery mildew was transferred from WB97 to sugar beet, and a series of germplasm releases identified as CP01, CP03, CP05, and CP07 were made (Lewellen 2000a, 2004a, b). Resistance is conditioned by one dominant gene (Lewellen and Schrandt 2001) (Figs. 8.12 and 8.13). WB242 (PI 546413) was obtained for the Salinas collection from Rietberg, Bergen op Zoom, the Netherlands in May 1974. It was reported to have been collected from the Loire River Estuary, France, and to have reduced nematode cyst counts in tests

Fig. 8.12 Segregation for reaction to Erysiphe polygoni within plot of CP04 with WB242 source 186 L. W. Panella et al.

Fig. 8.13 Adjacent 5-monts-old plants segregating for reaction to powdery mildew at IRS, Bergen op Zoom. It is probably similar to other accessions obtained from the Netherlands including one called Le Pouliguen Group 2 (PI 198758–59) received from Boss in 1987. Germplasm developed from the introgression of powdery mildew resistance into sugar beet from WB242 has been more extensively studied than that from WB97. Sequential backcrosses and improvements were released as germplasm lines CP02, CP04, CP06, CP08, and CP09CT (Lewellen 2000a, 2004a, b). Resistance to powdery mildew from WB242 is conditioned by one major gene named Pm (Lewellen and Schrandt 2001). Molecular markers to this resistance factor were identified (Janssen et al. 2003; Weiland and Lewellen 1999). WB242 is suscep- tible to rhizomania and backcrosses to introgress Pm into sugar beet utilized recurrent sugar beet lines that had resistance to rhizomania (Rz1). During field tests under both rhizomania and powdery mildew conditions, it was observed that derivatives from line CP02 also carried resistance/tolerance to sugar beet cyst nematode. Population CN12 was released as a source for resistance genes for powdery mildew (Pm), rhizo- mania (Rz1), and sugar beet cyst nematode in a background with adaptation for the Western USA (Lewellen 2006b). Other releases have included CN12-446, CN12- 751, CN12-770, CN12-8-407, CN07-410, CN07-413, and CN18-438 (Lewellen, unpublished). Although resistance to downy mildew caused by Peronospora fari- nosa (Fr.) Fr. f.sp. betae Byford (syn. Peronospora schachtii Fckl.) has been reported (Dale et al. 1985), we are not aware of any breeding programs using this source for commercial varieties. 8 Source of Useful Traits 187

8.1.6 Root Rots

Rhizoctonia crown and root rot of sugar beet (caused by Rhizoctonia solani Kühn) affects or threatens sugar beet-growing areas worldwide (Ahmadinejad and Okhovat 1976; Büttner et al. 2003;Herr1996; Ogata et al. 2000; Panella 2005c; Windels et al. 2009). In the USA, where it is registered for use, Quadris™ (an azoxystrobin fungicide) effectively controls this disease; however, the timing of application is critical (Stump et al. 2004). As crop rotations are shortened in the USA, Europe, and worldwide, this disease is becoming an increasing problem. Rhizoctonia root rot is best managed through an integrated program, based on resistant germplasm using good cultural practices and timely fungicide application (Herr 1996). In the 1950s, Gaskill (USDA-ARS at Fort Collins, Colorado) began a Rhizoctonia crown and root rot resistance breeding program primarily based on the Great Western Sugar Co. (GWS) sugar beet germplasm (Lewellen 1992; Panella 1998a). Schneider and Gaskill (1962) also were looking at introduced germplasm at that time. Although in their report most everything is described as Beta vulgaris (Schneider and Gaskill 1962), they comment that much of the material is annual, which suggests that if it is not Beta maritima, it had most likely hybridized with it at some point. Some of this Beta maritima germplasm made its way into SP5831, released for resistance to Aphanomyces black root (Doney 1995). This source, as well as other sources of Beta maritima, was incorporated into some of the early Rhizoctonia-resistant releases. These included FC706 (Hecker and Ruppel 1979), FC708 (Hecker and Rup- pel 1981), and FC710 (Hecker and Ruppel 1991; Panella 1998a, 2005c). Although commercial sugar beet breeding companies used and exchanged this germplasm, much of this activity was informal and it is not easy to document the use of Beta maritima (Lewellen 1992). Since the 1980s, efforts to screen Beta maritima for new sources of resistance to R. solani have increased (Asher et al. 2001b; Burenin 2001; Luterbacher et al. 2000, 2005; Panella and Frese 2003; Panella and Lewellen 2007). Most of the Rhizoctonia- resistant germplasm (commercial and public) can trace its parentage to the USDA- ARS program at Fort Collins, Colorado, started by Gaskill (Panella 2005c). This program continues to screen Beta maritima for resistance to Rhizoctonia solani and to incorporate resistant accessions into enhanced germplasm for release (Hanson and Panella 2002c, 2003c, 2004b, 2005, 2006, 2007; Panella 1999b, 2000c; Panella et al. 2008, 2010, 2011b, 2012, 2013, 2014, 2015a, 2016; Panella and Hanson 2001c; Panella and Ruppel 1998). Fusarium yellows is an important soilborne disease found in sugar beet (Beta vulgaris L.) production areas throughout sugar beet-growing areas worldwide (Christ and Varrelmann 2010; Panella and Lewellen 2005; Hanson et al. 2018). Many Fusar- ium species have been reported to cause Fusarium yellows (Hanson 2006; Hanson and Hill 2004; Hanson and Lewellen 2007; Ruppel 1991; Windels et al. 2009); how- ever, the primary causal agent in sugar beet is Fusarium oxysporum Schlechtend. Fr. f. sp. betae (Stewart) Snyd & Hans. (Stewart 1931). The severity of Fusarium yellows is influenced by temperature, inoculum dose, and presence of sugar beet 188 L. W. Panella et al. cyst nematode (Heterodera schachtii Schm.) (Gao et al. 2008; Hanson et al. 2009a, b; Landa et al. 2001). When conditions favor its occurrence, yield losses can be devastating (Hanson et al. 2009a, b). Unfortunately, F. oxysporum f. sp. betae is highly variable in its morphology, pathogenicity, and genetic structure (Harveson and Rush 1997; Hanson et al. 2018; Hill et al. 2011; Ruppel 1991). Other species of Fusarium also have been shown to cause yellowing-like symptoms on sugar beet (Burlakoti et al. 2012; Hanson and Hill 2004). Research to date has identified resistant commercial cultivars and a high degree of variability in virulence (Hanson et al. 2009a, b). Management of this disease is heavily dependent on the use of resistant hybrid cultivars (Franc et al. 2002; Hill et al. 2011). In sugar beet, F. oxysporum-resistant lines are known, but the genetic system that controls Fusarium diseases is still unclear (de Lucchi et al. 2017). Some public breeding has been done, and Beta maritima accessions do have resistance (Panella et al. 2015b). Currently, germplasms containing Beta maritima germplasm are being screened by the USDA sugar beet breeding program in Fort Collins, Colorado, and field resistance is correlated to molecular markers (unpublished data) linked with resistance to F. oxysporum f. sp. betae (de Lucchi et al. 2017).

8.1.7 Cercospora Leaf Spot

Cercospora leaf spot (CLS) caused by the Cercospora beticola Sacc. is the main fungal disease of beet-growing areas in temperate and humid environ- ments (Fig. 8.14) and affects approximately one-quarter of the cultivated acreage (Holtschulte 2000; Jacobsen and Franc 2009). Pioneering studies on genetic resis- tance to CLS began in the late 1800s, but only in the early 1900s did the efforts in hybridization and selection made by Munerati achieve the first results. No other source of resistance has been isolated against this disease and incorporated into sugar beet cultivars, except for the “C2 form”, which was active only against rarely dis- tributed strains (Lewellen and Whitney 1976). Therefore, the CLS-resistant varieties currently used are derived from crosses with Beta maritima obtained by Munerati (de Bock 1986). Mass selections on sea beet began on plants sown in cultivated soil, followed by inbreeding, with the main objective being to fix enough bienniality (Munerati et al. 1913b). Crosses with the sea beet were begun, first using predomi- nantly biennial lines, followed by a number of backcrosses to eliminate the negative traits of the wild parents (fangy and fibrous roots, tendency toward bolting, etc.). Fur- ther selections improved bolting resistance and, after 10 years, led to the release of the line RO581, which was considered the first substantially improved CLS-resistant line (Coons et al. 1955). The line was distributed to public and private breeding stations. The American variety US201 is cited as one of the oldest derived lines, together with the Italian Cesena R and Mezzano 71, the Polish Buszczynski CLR, the French Desprez RC2, and the Dutch Vanderhaven AC (Bongiovanni et al. 1958). The increased effort of the breeding companies has produced an improvement in sugar 8 Source of Useful Traits 189

Fig. 8.14 Drawing of beet moderately diseased by CLS (KWS Cercospora Tafel) yield and bolting resistance, which had been the main negative traits of the CLS- resistant varieties. With the recent breeding progress, sugar yield is today at similar levels to that of the susceptible varieties (Panella and Lewellen 2007) (Fig. 8.15). It has been estimated that a severe epidemic in the USA can cause up to a 42% loss of gross sugar (Smith and Ruppel 1973), or up to a 43% relative dollar loss (Shane and Teng 1992). In the USA, initial breeding efforts were based on inbred germplasm developed from Pritchard’s (1916) lines and other European lines (Coons 1936) along with germplasm selected by American Crystal in the Arkansas Valley of Colorado (Skuderna 1925). However, as this breeding effort was getting underway, there was another source of Cercospora resistance brought into the USA from Europe (Coons et al. 1955). This material had been seen by Coons in 1925 when it still had many of the undesirable traits from Beta maritima. It had been further developed by Italian breeders, and by the time Coons saw it again in 1935, it had been greatly improved (Coons et al. 1955). The Italian germplasm was incorporated into Great Western Sugar Company vari- eties GW 304 and GW 359 (source Cesena) and the USDA-ARS researchers also used “Mezzano 71” (Coons et al. 1955; Lewellen 1992). Brewbaker et al. (1950) also referred to breeding lines from some other crosses with European Beta mar- itima, as well as wild beet (most likely Beta maritima) out of California. Although it is not known if US 201 (PI 590678) developed from Mezzano 71 was ever used in a commercial hybrid (Lewellen 1992), it found its way into many of the ARS breeding programs (Panella 1998a). It is these early CLS-resistant germplasm pools 190 L. W. Panella et al.

Fig. 8.15 Performance of CN12 progenies under severe nematode conditions, Imperial Valley, May 2007. Individual plants from CN12 were selfed and the S1 progeny evaluated under severe nematode conditions in overwintered Imperial Valley. This picture contrasts the differences in reaction to SBCN under these conditions among sets of S3 lines that had been selected for NR (foreground) and nematode susceptibility (background) that formed the basis of Cercospora resistance breeding in the USA, and much of that resistance came from the Beta maritima sources out of Munerati’s program and, later, from the curly top germplasm that was added to the Cercospora breeding pools to incorporate resistance to these two important diseases. Further efforts at breeding for resistance in ARS to CLS were focused on combining CLS resistance with other disease resistances, mainly through inbreeding (Panella 1998a). These early breed- ing efforts have been reviewed in several publications (Coons 1975; Coons et al. 1955; Lewellen 1992; Panella and McGrath 2010; Skaracis and Biancardi 2000). In the last 40 years, because of the renewed interest in using Beta maritima as a genetic resource in sugar beet breeding, developing new sources of resistance to CLS has become an important goal. Efforts in the 1980s by the USDA-ARS Sugar Beet Crop Advisory Committee (now Crop Germplasm Committee—CGC) focused on evalu- ations of sea beet for resistance to CLS as one of the most important goals (Doney 1998). In Europe, innovative methods to introgress genes from sea beet into sugar beet were developed by Bosemark (1969, 1971, 1989), which lead to the efforts of the Genetics and Breeding Work Group of the IIRB to develop “buffer populations” for CLS resistance, as described by Frese et al. (2001) in an example for rhizomania. Efforts in evaluating Beta maritima in Europe and the United States were intensi- fied, and some of this germplasm with CLS resistance was discovered (Panella and Frese 2000). In the USA, sea beet germplasm has been screened by the Sugar Beet CGC since 1986 (Hanson et al. 2009a, b, 2010, 2011; Hanson and Panella 2002a, 2003a; Panella 1999c, 2000a; Panella and Hanson 2001a; Panella et al. 1998), and 8 Source of Useful Traits 191

Fig. 8.16 Nematode resistance in commercial hybrids derived from Beta maritima. In this picture, two commercial hybrids (SBCN susceptible on left, partially resistant on right) are shown in an Idaho, USA field under SBCN conditions (courtesy Betaseed, Inc). Hybrids with partial resistance to SBCN are now being commercially grown across the northern growing areas of USA. Unlike the Beta procumbens resistance, yield drag does not occur in the absence of Heterodera schachtii there are now 123 accessions in GRIN of Beta maritima that have been screened for resistance to CLS. Of these, 13 were rated as very resistant (3 < on a scale of 1 = no disease to 9 = dead) (USDA-ARS 2011b) (Figs. 8.16). The GENRES CT95 42 project in Europe evaluated 82 Beta maritima accessions, 10 of which were scored very resistant (3<; same scale) (Frese 2004a). Many of these accessions have been incorporated into breeding programs, which are being released to increase the genetic base of the CLS-resistant commercial varieties (Panella and Lewellen 2007; Panella et al. 2015b).

8.1.8 Polymyxa Betae

Polymyxa betae (Fig. 8.17) is the vector of numerous soilborne viruses of sugar beet (Abe and Tamada 1986; Kaufmann et al. 1992; Liu and Lewellen 2008; Wisler et al. 1994), including Beet necrotic yellow vein virus (BNYVV), the cause of rhizomania (Tamada and Baba 1973). BNYVV is transmitted by viruliferous zoospores of this plasmodiophorid protozoan. Polymyxa betae is an obligate parasite and is found in almost every soil in which sugar beet is grown (Liu and Lewellen 2007). Beet is infected by anterior bi-flagellate zoospores. Polymyxa betae forms long-living resting spores clustered together to form cystosori. Viruliferous cystosori can survive many decades in the field. The life cycle, ecology, and infection process have been well documented (Keskin 1964; Tamada and Asher 2016a, b). As a parasite per se, 192 L. W. Panella et al.

Fig. 8.17 Polymixa betae is the vector of BNYVV. Shown here are Patellifolia betae cystosori in sugar beet root cells (courtesy John Sears)

Polymyxa betae is usually not considered to cause measurable damage. However, in well-designed and controlled tests, it has been shown to cause reductions in yield (Liu and Lewellen 2008; Wisler et al. 2003). To quantify the level of Polymyxa betae in sugar beet roots, in addition to micro- scopic techniques, end-point PCR methods were developed (Mutasa et al. 1993, 1995, 1996). However, these methods only indicate Polymyxa betae’s presence or absence at one specific time. Moreover, the presence of DNA from non-infecting or dead zoospores attached to roots can give misleading results. Kingsnorth et al. (2003) developed protocols for both sequence-independent and hybridization probe real-time PCR for the detection of Polymyxa betae glutathione-S-transferase (GST) in infected sugar beet roots. They also demonstrated that real-time PCR analyses of both serially diluted zoospore suspensions and infected root material provided a close relationship between the threshold cycle and the amount of Polymyxa betae. One strategy for breeding more durable resistance to BNYVV is to combine virus resistance genes (e.g., Rz1, Rz2) (Sect. 8.1.3) with resistance to the vector, Polymyxa betae (Asher et al. 2009;Barretal.1995; Pavli et al. 2011). A two-gene system (Pb1/Pb2) conferring resistance against Polymyxa betae has been identified and mapped (Asher et al. 2009). The resistance to the vector is simply inherited and acts additively to the Rz1 resistance against BNYVV, while it also confers protection comparable to Rz1 in individuals lacking this gene. In research at Salinas by Liu and Sears, Kingsnorth’s methods were modified to screen Beta germplasm for possible resistance to Polymyxa betae (Liu, personal communication 2010). In a screen of germplasm, 38 materials were tested including accessions of Patellifolia procumbens, Patellifolia webbiana, and Patellifolia patel- laris. Four commercial hybrids received from KWS and Betaseed, Inc. (“Roberta” (rzrz), “Beta4430R” (Rz1), “Angelina” (Rz1Rz2), and “BetaG017R” (Rz2)), which 8 Source of Useful Traits 193 have been extensively used in rhizomania research at Salinas (Liu and Lewellen 2007, 2008; Liu et al. 2005), were used as checks. The remaining 31 entries repre- sented a broad germplasm base from the breeding program at Salinas and included rhizomania-resistant and rhizomania-susceptible sugar beet inbreds, populations, and open-pollinated lines. Many of the Salinas entries had germplasm from Beta maritima in their background. Based on the GST copy number, where lower values indicated more resistance or lower incidence of Patellifolia betae, there was a range from 9 to 881,000 copies. Patellifolia patellaris, Patellifolia procumbens, and Patellifolia webbiana were highly resistant to Polymyxa betae with an average of 52 copies. This agrees with previous findings (Paul et al. 1992, 1994). The four commercial hybrids ranged from 48,000 to 881,000 copies with “Angelina” being most susceptible. This result was supported by microscopic examinations, in which “Angelina” had the most cystosori. Except for three entries, the sugar beet lines fit in the same range of susceptibility. The exceptions were monogerm C790-15 (PI 564758) (Lewellen 1994), CP04 (PI 632285) (Lewellen 2004a), and monogerm C812-41 (PI 651522). C790-15 and CP04 were identical to Patellifolia accessions for copy number sug- gesting high resistance. C812-41 had ten times more copies and although partially inbred would likely segregate at most loci. These results need to be confirmed but suggest that high resistance may occur within sugar beet. C790-15 does not have known Beta maritima germplasm and is susceptible to rhizomania although in the field at Salinas showed tolerance (Lewellen, unpublished). C790-15 was selected in an S1 progeny, recurrent selection program that may have favored selection for resistance to Polymyxa betae, if genetic variability occurred. CP04 and C812-41 have germplasm from Beta maritima and resistance to rhizomania, Rz1 and Rz2 or Rz3, respectively. WB242 was the Beta maritima line used to breed CP04 (Sects. 8.1.5 and 8.1.11.1). C812-41 has WB41 and WB42 Beta maritima germplasm through C48 (PI 538251) (Lewellen and Whitney 1993) collected from Denmark and the source of the Rz2 and Rz3 resistance to BNYVV (Sect. 8.1.3). It is not known if this putative Polymyxa betae resistance came from sea beet or not. For C812-41, C790-15-type germplasm was used as the final sugar beet recurrent parent.

8.1.9 Black Root

Aphanomyces root rot or black root and Aphanomyces damping-off are caused by the oomycete, Aphanomyces cochlioides Drechs (Buchholtz and Meredith 1944; Drech- sler 1929). Black root is a chronic rot of the mature root, which can be a component of a root rotting complex, often including Fusarium yellows and Rhizoctonia crown and root rot (Harveson and Rush 2002). Aphanomyces root rot has been reported in Canada, Chile, Eastern Europe, France, Germany, Hungary, Japan, Russia (and the former Soviet Union), the UK, and the USA (Asher and Hanson 2006; Panella 2005a; Windels and Harveson 2009). Early Aphanomyces resistance breeding programs were centered in the Red River Valley (Minnesota and North Dakota, USA) and with the USDA-ARS stations at 194 L. W. Panella et al.

Beltsville, MD and East Lansing, MI. Progress was slow until a greenhouse screen- ing method was developed by Coe and Schneider (Coe and Schneider 1966; Doxtator and Downie 1948; Doxtator and Finkner 1954; Schneider 1954). In the early gen- erations of testing, curly top and leaf spot-resistant material found its way into this program, some of which contained a significant contribution from Beta maritima germplasm (this chapter). Schneider and Gaskill (1962) tested a number of foreign accessions (including some Beta maritima) for resistance. It is unknown how much of a contribution was made by resistance genes from sea beet. More recently, evaluations by the USDA-ARS Sugar Beet Crop Germplasm Com- mittee (CGC) and the European GENRES project (“Evaluation and enhancement of Beta collections for the extensification of agricultural production”— GENRES- CT95-42) have screened sea beet germplasm for resistance to Aphanomyces (Asher et al. 2001a; Doney 1998; Panella and Frese 2003). In the European evaluations of 159 accessions of Beta maritima, 5 had high resistance to Aphanomyces cochlioides (Luterbacher et al. 2005), and of the 87 screened by the USDA-ARS, 11 had high resistance to this disease (USDA-ARS 2011c). The USDA-ARS breeding program at East Lansing, MI, continues developing Aphanomyces-resistant germplasm and studying its inheritance (McGrath 2006;Yu2004).

8.1.10 Minor Fungal Diseases

High resistance to blackleg disease caused by Pleospora bjoerlingii Byford (Phoma betae Frank) was observed on fodder beets and on hybrids with Beta maritima (Burenin and Timoshenko 1985; Kazantseva 1975). Under severe attack of rust (Uromyces betae), Coons (1975) identified some Beta maritima population free from infection.

8.1.11 Nematodes

8.1.11.1 Cyst Nematodes

Sugar beet cyst nematode (SBCN) (Heterodera schachtii Schm.) is among the most damaging pests known on sugar beet worldwide. Major gene resistance has not been found in sugar beet germplasm (Doney and Whitney 1969). However, high resistance is well known in the Genus Patellifolia (formerly Section Procumbentes of Genus Beta) Ulbrich (Schneider 1937). Resistance from Patellifolia procumbens was transferred by Helen Savitsky to sugar beet as a 19-chromosome alien addition line reduced to 18 chromosomes containing a translocated fragment (Savitsky 1975, 1978) (Fig. 1.41). Similar interspecific hybrids have been made and advanced many times since (Jung et al. 1994). This nematode resistance was named Hs1pro-1 and has been cloned (Cai et al. 1997). The literature on nematode resistance from Patellifolia 8 Source of Useful Traits 195 procumbens has been reviewed (Jung et al. 1994; Panella and Lewellen 2007;Yu 2005). Commercial varieties using Hs1pro-1 have been developed by commercial seed companies but show a yield penalty under most cultural conditions (Lewellen and Pakish 2005). Resistance to nematode, in which there is no yield drag, remains needed. Among the Beta maritima accessions assembled at Salinas by McFarlane were several that had been reported to be partially resistant to SBCN or have reduced numbers of cysts (although we will refer to this as a “partial resistance” to SBCN, it is often referred to as tolerance rather than resistance) (Heijbroek et al. 1977). Among these was accession WB242 (PI 546413) (Sect. 8.1.5) that had been provided by Rietberg, IRS, Bergen op Zoom, the Netherlands in May 1974 and stated to be an accession collected from Loire River Estuary in France. The accessions with partial resistance were crossed with about 60 other individual sea beet accessions to sugar beet (Lewellen and Whitney 1993). The bulked F2s were placed in the USDA-ARS NPGS Beta collection (NSSL serial no. 206290). The F2s also were mass selected at Salinas under rhizomania conditions to produce a broadly based sugar beet × sea beet population called R22. R22 was released as C50 (PI 564243) (Lewellen and Whitney 1993). After five cycles of recurrent phenotypic selection, an improved R22 line released as C51 (PI 593694) was produced (Lewellen 2000b). The primary emphasis was selection for resistance to rhizomania and Virus Yellows. In 1995, an experimental hybrid with R22 was grown in an Imperial Valley of California test under rhizomania conditions in comparison to “Rhizosen” (Rz1 Holly Hybrids cultivar) and a rhizomania-susceptible commercial cultivar “HH41” that had been grown widely in Imperial Valley (Lewellen and Wrona 1997). As had been observed previously for R22 and R22 hybrids at Salinas, R22 and R22 hybrids seemed to express greater resistance to rhizomania than that conditioned solely by Rz1. It was unclear whether this greater resistance was due to improved resistance to rhizomania or resistance to some other pest or disease present in the field. Resistance to beet cyst nematode was suspected by JR Stander and RT Lewellen because most of the rhizomania trial areas also were infested with cyst nematode. Despite its 12.5% Beta maritima germplasm, the R22 hybrid had significantly higher sugar yield than Rhizosen (Lewellen and Wrona 1997). A field trial area was established on the Brawley Station, Imperial Valley of California (IV) for evaluation of reaction to rhizomania. Later, it became evident that the cyst nematode population also had increased and had become the predominant disease factor in this trial area (Becker et al. 1996). Since 1995, an expanded area has been successfully used to screen and select Beta germplasm resources and breeding lines for resistance to SBCN. During the later stages of development of C51, R22 was being backcrossed into self-sterile sugar beet breeding lines such as C78 (Lewellen 1997b). In the same 1995 trial with R22, some of these backcross-derived lines also were superior to lines with only Rz1, suggesting that the factor from R22 for enhanced performance or disease resistance had been further introgressed into sugar beet and was highly heritable and efficacious. Line C67/2 (PI 628750) (about 6% Beta maritima) (Lewellen 2004c) and C72 (PI 599342) (about 3% Beta maritima) were as resistant as R22. Based upon subsequent greenhouse tests, it was shown that cyst counts were highly correlated 196 L. W. Panella et al.

Table 8.3 Performance of a C927-4 experimental hybrid under non-diseased and severe sugar beet cyst nematode (SBCN) conditions in the Imperial Valley of California in comparison to commercial hybrids Variety Rz1, Rz1,R22(Bvm) Severe SBCN Non-SBCN SYa (kg/ha) Appearanceb SY (kg/ha) US H11 3800 3.3 Beta 4430R Rz1 7800 3.1 15,200 Phoenix Rz1 6300 3.8 14,300 C927-4H5 Rz1, R22 (Bvm) 11,200 1.8 13,200

LSD(0.05) 1900 0.7 1800 aSY is refined white sugar yield bAppearance is scored from 1 (healthy) to 5 (dead) with canopy appearance scores in the IV (higher scores for greater canopy loss); sugar yield was significantly, inversely correlated with canopy scores and cyst counts (Lewellen and Pakish 2005). From these tests, it was determined that the superior performance of R22 and populations extracted from it was due to partial resistance to Heterodera schachtii and that this differential canopy response gave a reliable way to identify and discriminate SBCN resistance from susceptibility. Crosses and backcrosses from R22 to C931 (Lewellen 2006a) to produce a self- fertile Doggett-type population were made to transfer Beta maritima-derived rhizo- mania resistance to sugar beet. Large numbers of individual plants were selfed to produce selfed progeny lines for evaluation. One of the specific lines with enhanced performance was released as C927-4 (PI 640421) (Lewellen 2004d). Subsequent tests in Imperial Valley and at Salinas in the field and greenhouse showed that C927-4 performance has been due in part to resistance to SBCN (Table 8.3). From C927-4, a series of selfed progeny lines were developed and tested for resistance to SBCN. Based on nematode tests under field and greenhouse conditions, CN927-202 (PI 640420) was selected from C927-4 and released (Lewellen 2007). From other backcrosses to sugar beet populations derived from R22, another selfed progeny line was found that had partial resistance to SBCN. This line was ultimately released as CN926-11-3-22 (PI 640421) (2% Beta maritima) after two additional cycles of selfing and reselection for resistance to SBCN (Fig. 1.44) (Lewellen 2007). From two different sugar beet × Beta maritima broadly based populations called C26 (PI 610488) and C27 (PI 610489) (Lewellen 2000b), a selfed progeny line from a backcross to C931 was identified that appeared to be resistant to SBCN. This nematode-tolerant line was the only one identified from this material and was released as CN921-306 (PI 640422) (25% Beta maritima) (Lewellen 2007). The specific accession(s) among the Salinas collection of sea beet lines that con- tributed the resistance gene(s) for cyst nematode resistance to R22 was not known. One of the logical candidates was WB242, which was being used concurrently in the powdery mildew (Sect. 8.1.5) resistance genetics and breeding program (Lewellen 2000a; Lewellen and Schrandt 2001). For the powdery mildew research, WB242 8 Source of Useful Traits 197 and WB97 (PI 546394) were crossed and backcrossed to sugar beet to set up a Doggett population. When individual plants of this population were examined and selected, it was observed that in addition to segregation for reaction to powdery mildew (Pm_:pmpm), some root systems were heavily infested with SBCN cysts, whereas intermingled roots from some adjacent plants were completely free of vis- ible cysts. As mother roots and stecklings were being advanced from sequential backcrosses to sugar beet for resistance to Erysiphe polygoni and rhizomania, the root system of each plant was also examined and, where possible, preference was given for seed production to ones without nematode cysts. Within the population that became P912, there appeared to be a low frequency of SBCN-resistant plants. Similar selections originating with WB242 lead to CP04, CP06, CP07, and CP08 (Lewellen 2004a, b). When evaluated under the Imperial Valley conditions, these progressions of backcross lines from WB242 germplasm showed similar performance for resis- tance to SBCN as R22- and R22-derived material (Lewellen and Pakish 2005). P912 was released as CN12 (Lewellen 2006a, b). From CN12, individual selfed progeny lines were evaluated and selected (Fig. 8.16). Some of these have been released as CN12-446 (PI 657939) and CN12-770 (PI 657940). In an informal exchange of breeding lines for disease resistance, an accession of Beta maritima was received from IRS, the Netherlands in 1987. This accession was reported to be Le Pouliguen Group 2 PI 198758–59. Le Pouliguen Group 2 had been selected for low SBCN cyst counts from Beta maritima collected from Le Pouliguen, Brittany, France by Cleij and coworkers at IRS, Bergen op Zoom and SVP, Wageningen (Hijner 1951; Lange and de Bock 1994). These materials were shown to have partial resistance to SBCN but initially thought not to be useful in sugar beet breeding (Heijbroek 1977; Heijbroek et al. 1977). Repeated selection was carried out, and rather high levels of resistance were achieved (Mesken and Lekkerkerker 1988). In 1990, several of the selected stocks were released to the European breeding companies (Lange and de Bock 1994). In tests at Wageningen by Lange and de Bock (1994), it was found that the resistant selections from this Beta maritima reduced the number of cysts by about two-thirds. In addition, it was shown that the Beta maritima resistance resulted in many of the cysts being much smaller than those on the susceptible control varieties. These smaller cysts contained fewer eggs and reduce the multiplication rate of the nematodes even further. Greenhouse tests at Salinas showed Le Pouliguen Group 2 to have reduced cyst counts as compared to susceptible sugar beet. Although Le Pouliguen Group 2 did not enter the breeding program at Salinas, it was believed to be similar to WB242 and corroborated the value of partial resistance in Beta maritima. Eight years later, similar Beta maritima material called accession N499 (PI 599349) at Salinas was obtained from KWS seed company. After initial tests in the field at Salinas and Brawley, CA under SBCN conditions, this weedy appearing annual sea beet was backcrossed into sugar beet population C931. An improved population was released as CN72 (PI 636339) (Lewellen 2006b). From CN72, individual selfed progeny families were evaluated at Salinas and Brawley and one line was released as CN72-652 (PI 657938). The SBCN partial resistance from this Beta maritima source from Le Pouliguen, France progressed to commercial 198 L. W. Panella et al.

Fig. 8.18 Field trials in Imperial Valley of California are used to select and evaluate reactions to cyst nematode usage in hybrids developed by KWS and Betaseed, Inc. to ameliorate the damage caused by Heterodera schachtii (Fig. 8.18). The genetic relationship for resistance to SBCN from Beta maritima among R22 populations, WB242, CN12, Le Pouliguen Group 2, and N499 (CN72) is now known (Stevanato et al. 2014b). Because most of these lines and sources have been derived from the Loire River Estuary in France, all seem have the same gene for SBCN resis- tance. Nonetheless, WB242 has high resistance to Erysiphe polygoni (Pm) and has a compact, dark green canopy with slow bolting tendency that distinguishes it from the SBCN resistance from the other sources, particularly N499. In Imperial Valley tests, it appears that partial resistance to Empoasca sp. also may occur in WB242-derived material. The SBCN resistance derived from Beta maritima is not immunity, but con- ditions lowered reproduction of cyst nematode (Lange and de Bock 1994; Lewellen and Pakish 2005) and greatly reduces the losses caused by Heterodera schachtii under field conditions (Lewellen and Pakish 2005). Similar resistance from Beta maritima has been advanced by the commercial seed companies into commercial hybrids and shows equally favorable resistance without sugar yield drag associated with the Beta procumbens source under commercial sugar beet production. Many technologies have been developed to very quickly genotype large num- bers of SNPs in DNA samples (Stevanato et al. 2014a). SNP markers linked to the nematode tolerance were developed using the WB242 source. A segregating F2 pop- ulation, developed from WB242 as pollinator was crossed to a male sterile line was used for bulked segregant analysis to develop an SNP marker linked to the gene for 8 Source of Useful Traits 199 sugar beet nematode tolerance, named HsBvm-1 (Pegadaraju et al. 2013; Stevanato et al. 2014b). This marker was able to select among a set of 13 tolerant (heterozygous for the marker) and 13 susceptible commercial (homozygous susceptible) as well as the homozygous-resistant F2 plants (Stevanato et al. 2014b). These results have been confirmed in another segregating F2 population with WB242 as the resistance donor parent (unpublished data).

8.1.11.2 Root-Knot Nematodes

Damage from root-knot nematode (RKN) caused by numerous species of Meloidog- yne is common where sugar beet is grown in a subtropical or warm temperate climate. Resistance to RKN could not be found in cultivated Beta vulgaris in a screen of 190 accessions (Yu 1995) (Fig. 1.45). In an initial search of 113 Beta maritima acces- sions, resistance was identified in WB66 (PI 546387). The original source of WB66 is unknown but likely was found within a collection from Wageningen (WB37) in 1963 by way of the Japan Sugar Beet Improvement Foundation in 1968. Resistance from WB66 has been transferred to sugar beet (Yu 1996, 2001;Yuetal.1999, 2001; Yu and Lewellen 2004). An isozyme marker was identified for RKN resistance (Yu et al. 2001). Beet germplasm with resistance initially was released and registered as germplasm line M66 (Yu 1996). A molecular marker was identified, and the inheritance of resistance was shown to be conditioned by a single dominant gene named R6m-1 (Weiland and Yu 2003). Subsequently, resistant beet germplasm from backcrosses to sugar beet was released as M6-1 (Yu 2001). An additional release was made following the fifth backcross to sugar beet after homozygous-resistant plants were selected (Yu and Lewellen 2004). The R6m-1 gene in lines M66, M6-1, and M6-2 has been shown to condition resistance to at least six species of Meloidogyne (Yu et al. 1999; Yu and Roberts 2002). Resistance to RKN was also discovered in WB258 (PI 546426) (Yu 1997, 2002a, b). WB258 was collected by de Biaggi and Biancardi in the Po Delta in 1979 and sent to McFarlane at Salinas (step 12, Sect. 1.7). WB258 was also shown to have resistance to rhizomania (Lewellen 1995a, 1997a; Whitney 1989c) (Sect. 8.1.3). Root-knot nematode resistance from WB258 is near immunity and conditions resistance to all Meloidogyne species tested (Yuet al. 1999). Resistance from WB258 and WB66 may or may not be the same, whereas resistance from WB66 is marked by an isozyme (Yu et al. 2001), which from WB258 is not (Yu 2002b). This difference suggests that WB66 and WB258 were collected from different locations and populations. Resistance to root-knot nematode may be essential in the development of sugar beet for subtropical areas, where Meloidogyne spp. cause severe losses. 200 L. W. Panella et al.

8.1.12 Insects

In Beta maritima, some degree of resistance has been found to bean aphid (Aphis fabae) colonization (Dale et al. 1985) and to the multiplication rate of green peach aphid (Myzus persicae) (Lehmann et al. 1983). Lowe and Russell (1969) ascertained that the resistance to aphids is inherited in pattern suggesting a trait under polygenic control. These findings have not led to any practical application.

8.1.13 Multiple Resistances

The diseases of beet crops may appear alone or, more frequently, associated with one another. In this case, genotypes endowed with multiple resistances would be useful (McFarlane 1971), and, indeed many hybrids are multiple disease resistances. Many recent public germplasm releases, multigerm, monogerm, and O-type lines, have multiple disease resistances (e.g., Lewellen 2006b; Panella and Lewellen 2005; Panella et al. 2011a, 2015). These materials were crossed with genotypes bearing the monogenic resistances to rhizomania taken from Beta maritima. Luterbacher et al. (2005, 2004) published the results of a large survey including cultivated and wild germplasm belonging to the genus Beta. Between 580 and 700 accessions were evaluated in several European countries in the presence of three foliar diseases (VYs, powdery mildew, Cercospora leaf spot). The assessment of resistances was performed both in field and glasshouse conditions. In taxa within section Beta, there were some cases of multiple resistances identified in Beta maritima. The rate of entries displaying more than one resistance was higher in the genus Patellifolia and section Corollinae. Regarding the soilborne diseases caused by Aphanomyces cochlioides, Pytium ultimum, Rhizoctonia solani, and BNYVV, Beta maritima showed the highest number of accessions endowed with multiple resistances. By this term, Scholten et al. (1999) also mean the combination in the same genotype of different types of resistance to the single disease. The combination of diverse resistances increases the plant’s ability to combat the effects of the disease with complementary reaction mechanisms (Lewellen and Biancardi 1990). This synergy is currently employed for contrasting the yield reduction in severe rhizomania diseased fields (Sect. 8.1.3).

8.2 Resistances to Abiotic Stresses

Surveys conducted on commercial varieties of sugar beet have shown the existence of a reduced genetic variability for tolerance to water stress. The physiological basis of salt resistance in Beta maritima has been explored by Koyro (2000) and Bor et al. (2003). The habitat of Beta maritima requires resistance to abiotic stresses caused by both salinity and drought (Shaw et al. 2002). These traits are ones that 8 Source of Useful Traits 201 have been sought in sugar beet for many years (reviewed by van Geyt et al. 1990), especially in climates where sugar beet cultivation is rain-fed. The effect of climatic and precipitation patterns on rain-fed sugar beet production areas in Europe has been studied (Pidgeon et al. 2001), and there is concern on the effect that global climate change will have on continued production (Jones et al. 2003; Pidgeon et al. 2004).

8.2.1 Drought and Heat Tolerance

Drought tolerance has long been of interest to sugar beet breeders (van Geyt et al. 1990) and is one of the often-mentioned rationales for conserving and using Beta maritima as a genetic resource of sugar beet (Doney and Whitney 1990;Frese 2003, 2004b; Stevanato et al. 2004). Because of the variability of rainfall in the UK, researchers there have long been interested in drought tolerance in sugar beet and Beta maritima germplasm, and in developing assays to determine drought toler- ance (Thomas et al. 1993). The GENRES CT95 42 project in Europe evaluated 155. Beta maritima accessions (Frese 2004a). In this test, a standard was used, the cultivar “Saxon”, and data from all accessions that were significantly different in weight than Saxon were normalized to Saxon and the deviation from the mean for individual accessions was divided intoa1to9scalewith1asthemosttolerant(Frese2004a). Five of the seven most drought-tolerant accessions (scored 1) were Beta maritima as were three with a drought stress score of 2 (Fig. 8.19). The drought screening was done at Broom’s Barn Research Station in the UK and much of the subsequent investigations and reporting out of these results have been done by scientists located there (Ober et al. 2004a, b, 2005; Ober and Rajabi 2010; Ober and Luterbacher 2002).

Fig. 8.19 Drought stress tolerance frequency distribution (Frese 2004a) 202 L. W. Panella et al.

Some researchers working with Beta maritima are approaching the issue from exam- ining the life history traits of the sea beet and how these traits, including resistance to drought, have evolved over time as important survival traits (Hautekèete et al. 2002, 2009; Wagmann et al. 2010). Although many of the countries, which grow winter beet in the Mediterranean and other heat and drought-stressed areas, are very inter- ested in drought tolerance, only a few are working actively with sea beet (Srivastava et al. 2000).

8.2.2 Salinity Tolerance

The resistance of Beta maritima to salt stress is well known and in the early 1980s this trait was used as an indicator of Beta maritima gene flow into ruderal beet populations (Evans and Weir 1981). Research has examined betaine accumulation and its relation to salinity comparing sugar beet with Beta maritima (Hanson and Wyse 1982). More recent work has compared the effect of salinity on lipid peroxidation and antioxidants in the leaves of sea beet and sugar beet (Bor et al. 2003;Koyro2000) and evaluated the osmotic adjustment response between the two taxa to try and understand the response to salinity (Bagatta et al. 2008; Koyro and Huchzermeyer 1999). There is an increasing interest in halophytic crops because the world’s supply of freshwater is shrinking and world population growing (Baydara 2008). If more saline water can be used to produce food, it will make available more freshwater for human consumption. There is an interest in using Beta maritima as a model system, a potential donor of salt tolerance genes, and even as a potential halophytic cash crop (Koyro et al. 2006; Koyro and Lieth 2008). Sugar beet is not the only crop that could benefit from the salt resistance in the sea beet genome; there is also interest in developing more salt-tolerant fodder beet cultivars (Niazi et al. 2000, 2005; Rozema et al. 1990). This response to saline soils is especially important to areas in the Mid- Eastern and North African areas where both heat and salinity of irrigation water are a problem. Recent work in Egypt looked at gene expression in relation to salt stress (El-Zohairy et al. 2009). Although sugar beet is well adapted to saline areas when compared to other crop plants, at germination it is equally sensitive to saline conditions. Research has looked at gene expression and phenotypic differences in sugar beet and sea beet during this critical time of crop establishment (McGrath et al. 2008; Panella and Lewellen 2007).

8.3 Other Traits

According to Krasochkin (1959) and many other authors, Beta maritima collected in the northern sites should be an important resource for increasing the sugar content in sugar beet. Campbell (1989) selected 30 sea beets with very high sugar content in good correlation with the root weight. Dale et al. (1985) ascertained that in sea beet 8 Source of Useful Traits 203 accessions there were plants developing male sterile flowers. These plants produced seed if individually crossed with normal pollen producers of the same accession, thus suggesting the presence of the O-type trait or CMS in Beta maritima populations (Sect. 3.10). What is important to remember is that we can never with certainty predict what traits will be of importance in the future. Populations of sea beet existing in situ, undergoing continual coevolution with pests, disease, and the environment, are our insurance policy that we will have the genetic resources to fill future needs (this chapter).

References

Abe H, Tamada T (1986) Association of beet necrotic yellow vein virus with isolates of Polymyxa betae Keskin. Ann Phytopathol Soc Jpn 52:235–247 Abegg FA (1936) A genetic factor for the annual habit in beets and linkage relationship. J Agr Res 53:493–511 Achard FC (1803) Anleitung zum Anbau der zur Zuckerfabrication anwendbaren Runkelrüben und zur vortheilhaften Gewinnung des Zuckers aus denselben. Reprinted in: Ostwald’s Klassiker der exacten Wissenschaft (1907). Engelmann, Leipzig, Germany Ahmadinejad A, Okhovat M (1976) Pathogenicity test of some soil-borne fungi on important field crops. Iran J Plant Pathol 12:10–18 Amiri R, Mesbah M, Moghaddam M, Bihamta MR, Mohammadi SA, Norouzi P (2009) A new RAPD marker for beet necrotic yellow vein virus resistance gene in Beta vulgaris. Biol Plant 53:112–119 Asher MJC, Hanson LE (2006) Fungal and bacterial diseases. In: Draycott AP (ed) Sugar beet. Blackwell, Oxford, UK, pp 286–315 Asher MJC, Luterbacher MC, Frese L (2001a) Wild Beta as a source of resistance to sugar-beet pests and diseases. In: Proceedings of the 64th IIRB congress. Bruges (B), pp 141–152 Asher MJC, Luterbacher MC, Frese L (2001b) Wild Beta species as a source of resistance to sugar- beet pests and diseases. In: Proceedings of the 64th congress of the IIRB, 2001. IIRB, Brussels, pp 141–152 Asher MJC, Grimmer MK, Mutasa-Goettgens ES (2009) Selection and characterization of resistance to Polymyxa betae, vector of Beet necrotic yellow vein virus, derived from wild sea beet. Plant Path 58:250–260 Azorova M, Subikova V (1996) The modified procedure of ELISA for detection of BNYVV. Listy Cukrovarnicke a Reparske 112:297–300 Bagatta M, Pacifico D, Mandolino G (2008) Evaluation of the osmotic adjustment response within the genus Beta. J Sugar Beet Res 45:119–133 Barr KJ, Asher MJC, Lewis BG (1995) Resistance to Polymyxa betae in wild Beta species. Plant Path 44:307 Bartsch D, Clegg J, Ellstrand N (1999) Origin of wild beets and gene flow between Beta vulgaris and B. macrocarpa in California. Proc Br Crop Prot Counc Symp 72:269–274 Barzen E, Stahl R, Fuchs E, Borchardt DC, Salamini F (1997) Development of coupling-repulsion phase SCAR markers diagnostic for the sugar beet Rz1 allele conferring resistance to rhizoma- nia. Mol Breed 3:231–238 Baydara EP (2008) Salt stress responsive proteins identification in wild sugar beet (Beta maritima) by mass spectrometry. Thesis Ìzmir Institute of Technology, Izmir, Turkey Becker JO, Wrona AF, Lewellen RT (1996) Effect of solarization and soil fumigation on sugarbeet cyst nematode population, 1993–1995. Biol Cult Tests Control Plant Dis 11:19 Bennett CW (1960) Sugar beet yellows disease in the United States. US Dep Agr Bull 1218:1–63 204 L. W. Panella et al.

Bennett CW (1971) The curly top disease of sugarbeet and other plants. The American Phytopatho- logical Society, St. Paul, MN, USA Bennett CW, Leach LD (1971) Diseases and their control. In: Johnson RT, Alexander JT, Rush GE, Hawkes GR (eds) Advances in sugarbeet production: principles and practices. The Iowa State University Press, Ames, Iowa (USA), pp 223–285 Bennett CW, Tanrisever A (1958) Curly top disease in Turkey and its relationship to curly top in North America. J ASSBT 10:189–211 Biancardi E, Lewellen RT, de Biaggi M, Erichsen AW, Stevanato P (2002) The origin of rhizomania resistance in sugar beet. Euphytica 127:383–397 Biancardi E, McGrath JM, Panella LW, Lewellen RT, Stevanato P (2010) Sugar beet. In: Bradshaw JE (ed) Root and tuber crops. Springer, New York, NY USA, pp 173–219 Biancardi E, Tamada T (ed) (2016) Rhizomania. Springer Science + Bussiness Media, LLC, New York, NY, pp 281 Bongiovanni GC (1964) La diffusione della rizomania in Italia. Informatore Fitopatologico 10:265 Bongiovanni GC, Gallarate G, Piolanti G (1958) La Barbabietola da Zucchero. Edagricole, Bologna, Italy Bor M, Özdemir F, Türkan I (2003) The effect of salt stress on lipid peroxidation and antioxidants in leaves of sugar beet Beta vulgaris L. and wild beet Beta maritima L. Plant Sci 164:77–84 Bosemark NO (1969) Interspecific hybridization in Beta vulgaris L.: prospects and value in sugar- beet breeding. J IIRB 4:112–122 Bosemark NO (1971) Use of Mendelian male sterility in recurrent selection and hybrid breeding in beets. Eucarpia Fodder Crops Section, Report of Meeting, Lusigan, France, pp 127–136 Bosemark NO (1979) Genetic Poverty of the sugar beet in Europe. In: Zeven AC (ed) Proceedings of the conference broadening genetic base of crops. Pudoc, Wageningen, The Netherlands, pp 29–35 Bosemark NO (1989) Prospects for beet breeding and use of genetic resources. In: Report on an international workshop on beta genetic resources, Wageningen (the Netherlands), 7–10 Feb 1989. International Crop Network Series. 3. IBPGR, Rome, pp 89–97 Brewbaker HE, Bush HL, Wood RR (1950) A quarter century of progress in sugar beet imporvement by the Great Western Sugar Company. Proc ASSBT 6:202–207 Briddon RW, Stenger DC, Bedford ID, Stanley J, Izadpanah K, Markham PG (1998) Comparison of a beet curly top virus isolate originating from the old world with those from the new world. Eur J Plant Path 104:77–84 Brunt AA, Richards KE (1989) Biology and molecular biology of furoviruses. Adv Virus Res 36:1–32 Buchholtz WF, Meredith CH (1944) Pathogensis of Aphanomyces cochlioides on taproots of the sugar beet. Phytopathology 34:485–489 Burlakoti P, Rivera V, Secor GA, Qi A, Del Rio-Mendoza LE, Khan MFR (2012) Comparative pathogenicity and virulence of Fusarium species on sugar beet. Plant Dis 96:1291–1296 Burenin VI (2001) Genetic resources of sugarbeet and resistance to diseases (in Russian). Sakhar- naya Svekla 7:25–29 Burenin VI, Timoshenko ZV (1985) Blackleg resistance in beet (in Russian). Genet Selek 92:56–62 Büttner G, Pfähler B, Petersen J (2003) 2003: Rhizoctonia root rot in Europe—incidence, economic importance and concept for integrated control. In: Proceedings of the international institute of beet research 1st joint IIRB-ASSBT congress, 26th Feb–1st Mar 2003, San Antonio, USA, pp 897–901 Cai D, Kleine M, Kifle S, Harloff HJ, Sandal NN, Marcker KA, Klein-Lankhorst RM, Salentijn EMJ, Lange W, Stiekema WJ, Wyss U, Grundler FMW, Jung C (1997) Positional cloning of a gene for nematode resistance in sugar beet. Science (Washington) 275:832–834 Campbell LG (1989) Beta vulgaris NC-7 collection as a source of high sucrose germplasm. J Sugar Beet Res 26:1–9 Campbell LG (2010) Registration of seven sugarbeet germplasms selected from crosses between cultivated sugarbeet and wild Beta species. J Plant Reg 4:149–154 8 Source of Useful Traits 205

Canova A (1966) Ricerche virologiche nella rizomania della bietola. Rivista Patologia Vegetale 2:3–41 Carsner E (1926) Resistance in sugar beets to curly top. USDA Circ 388:7 Carsner E (1928) The wild beet in California. Facts About Sugar 23:1120–1121 Carsner E (1933) Curly-top resistance in sugar beets and test of the resistant variety U.S. no. 1. USDA Technical. Bulletin 360:68 Christ DS, Varrelmann M (2010) Fusarium in sugarbeet. Zuckerind 136:161–171 Coe GE, Hogaboam GJ (1971) Registration of sugarbeet parental line SP 6322–0. Crop Sci 11:947 Coe GE, Schneider CL (1966) Selecting sugar beet seedlings for resistance to Aphanomyces cochlioides. J ASSBT 14:164–167 Coons GH (1936) Improvement of the sugar beet. 1936 Yearbook of Agriculture. USDA, Washing- ton, DC, USA, pp 625–656 Coons GH (1953) Some problems in growing sugar beets. Yearbook of Agriculture, USDA, Wash- ington, DC, USA, pp 509–524 Coons GH (1975) Interspecific hybrids between Beta vulgaris L. and the wild species of Beta.J ASSBT 18:281–306 Coons GH, Stewart D, Elcock HA (1931) Sugar-beet strains resistant to leaf spot and curly top. Yearbook of Agriculture, pp 493–496 Coons GH, Owen FV, Stewart D (1955) Improvement of the sugar beet in the United States. Adv Agron 7:89–139 Dale MFB, Ford-Lloyd BV, Arnold MH (1985) Variation in some agronomically important char- acters in a germplasm collection of beet (Beta Vulgaris L.). Euphytica 34:449–455 de Biaggi M (2005) Beet yellows. In: Biancardi E, Campbell LG, Skaracis GN, de Biaggi M (eds) Genetics and breeding of sugar beet. Science, Enfield (NH), USA, p 367 de Biaggi M (1987) Mehodes de selection—un cas concret. In: Proceedings of the 50th winter congress of the IIRB. IIRB Brussels, Belgium, pp 157–161 de Biaggi M, Erichsen AW, Lewellen RT, Biancardi E (2003) The discovery of rhizomania resistance traits in sugar beet. In: Proceedings of the international institute of beet research 1st joint IIRB- ASSBT congress, 26th Feb–1st Mar 2003, San Antonio, USA, pp 131–147 de Bock TSM (1986) The genus Beta: domestication, and interspecific hybridization for plant breeding. Acta Hort 182:335–343 de Lucchi C, Stevanato P, Hanson L, McGrath M, Panella L, de Biaggi M, Broccanello C, Bertag- gia M, Sella L, Concheri G (2017) Molecular markers for improving control of soil-borne pathogen Fusarium oxysporum in sugar beet. Euphytica 213: 71. https://doi.org/10.1007/s10681- 017-1859-7 Doney DL (1993) Broadening the genetic base of sugarbeet. J Sugar Beet Res 30:209–220 Doney DL (1995) USDA-ARS sugarbeet releases. J Sugar Beet Res 32:229–257 Doney DL (1998) Beta evaluation and sugar beet enhancement from wild sources. In: Frese L, Panella L, Srivastava HM, Lange W (eds) International Beta genetic resources network. A report on the 4th international Beta genetic resources workshop and world Beta network conference held at the Aegean agricultural Research Institute, Izmir, Turkey, 28 Feb–3 Mar 1996. International crop network series no. 12. International plant genetic resources institute, Rome, pp 62–72 Doney DL, Whitney ED (1969) Screening sugarbeet for resistance to Heterodera schachtii Schm. J ASSBT 15:546–552 Doney D, Whitney E (1990) Genetic enhancement in Beta for disease resistance using wild rela- tives: a strong case for the value of genetic conservation. Econ Bot 44:445–451 Doxtator CW, Downie AR (1948) Progess in breeding sugar beets for resistance to Aphanomyces root rot. Proc ASSBT 5:130–136 Doxtator CW, Finkner RE (1954) A summary of results in the breeding for resistance to Aphanomyces cochlioides (Drecks) by the American Crystal Sugar Company since 1942. Proc ASSBT 8:94–98 Drechsler C (1929) The beet water mold and several related root parasites. J Agr Res 38:309–361 Duffus JE (1973) The yellowing virus diseases of beet. Adv Virus Res 18:347–386 206 L. W. Panella et al.

Duffus JE, Liu H-Y (1991) Unique beet western yellows virus isolates from California and Texas. J Sugar Beet Res 28:68 Duffus JE, Ruppel EG (1993) Diseases. In: Cooke DA, Scott RK (eds) The sugar beet crop. Chapman & Hall, Cambridge, UK, pp 346–427 Duffus JE, Whitney ED, Larsen RC, Liu HY, Lewellen RT (1984) First report in western hemi- sphere of rhizomania of sugar beet caused by Beet necrotic yellow vein virus. Plant Dis 68:251 Dusi AN, Peters D (1999) Beet mosaic virus: vector and host relationships. J Phytopathol 147:293– 298 El-Zohairy S, El-Awady A, Eissa HF, El-Khishin DA, Nassar A, McGrath JM (2009) Differential expression of salt stress-related genes in wild Beta vulgaris. Egypt J Genet Cytol 38:187–206 Evans A, Weir J (1981) The evolution of weed beet in sugar beet crops. Genet Res Crop Evol 29:301–310 Fischer HE (1989) Origin of the ‘Weisse Schlesische Rübe’ (white Silesian beet) and resynthesis of sugar beet. Euphytica 41:75–80 Ford-Lloyd BV, Maxted N, Kell S (2009) Prioritization of wild Beta species for conservation: the PGR forum experience. In: Frese L, Maggioni L, Lipman E (eds) Report of a working group on Beta and the world Beta network. Third Joint Meeting, 8–11 Mar 2006, Puerto de la Cruz, Tenerife, Spain. Bioversity International, Rome, Italy Franc GD, Harveson RM, Kerr ED, Jacobsen BJ (2002) Disease management p. 131–160 in Sug- arbeet Production Guide, University of Nebraska, Lincoln, p 210 Francis SA, Luterbacher MC (2003) Identification and exploitation of novel disease resistance genes in sugar beet. Pest Manag Sci 59:225–230 Frese L (2003) Sugar beets and related wild species—from collecting to utilisation. In: Knüpffer H, Ochsmann J (eds) Schriften zu Genetischen Ressourcen, vol 22. Zentralstelle für Agrardoku- mentation und -information (ZADI). Bonn, Germany pp, pp 170–181 Frese L (2004a) Evaluation and enhancement of Beta collections for extensification of agricultural production, In: GENRES CT95 42. Final project report, Reporting period: 1996–2002. Federal centre for breeding research on cultivated plants (BAZ), Braunschweig, Germany, pp 1–114 Frese L (2004b) Rationale for in situ management of wild Beta species. Crop Wild Relative 2:4–7 Frese L (2010) Conservation and access to sugar beet germplasm. Sugar Tech 12:207–219 Frese L, Germeier CU (2009) The international database for Beta and in situ management—poten- tial, role and functions. In: Frese L, Maggioni L, Lipman E (eds) Report of a working group on Beta and the world Beta network. Third joint meeting, 8–11 Mar 2006, Puerto de la Cruz, Tenerife, Spain. Bioversity International, Rome, Italy, pp 59–74 Frese L, Desprez B, Ziegler D (2001) Potential of genetic resources and breeding strategies for base-broadening in Beta. In: Cooper HD, Spillane C, Hodgkin T (eds) Broadening the genetic base of crop production. FAO, IBPRGI jointly with CABI, Rome, Italy, pp 295–309 Friesen TL, Weiland JJ, Aasheim ML, Hunger S, Borchardt DC, Lewellen RT (2006) Identification of a SCAR marker associated with Bm, the beet mosaic virus resistance gene, on chromosome 1 of sugar beet. Plant Breed 125:167–172 Fujisawa ST (1976) Transmission of Beet necrotic yellow vein virus by Polymyxa betae.Ann Phytopathol Soc Jpn 43:583–586 Gao X, Yin B, Borneman J, Becker JO (2008) Assessment of parasitic activity of Fusarium strains obtained from a Heterodera schachtii-suppressive soil. J Nematol 40:1–6 Gentili P, Poggi G (1986) Ritmo, esperienze italiane contro rizomania e cercospora. Maribo, Bologna, Italy Geyl L, Garcia Heriz M, Valentin P, Hehn A, Merdinoglu D (1995) Identification and characteriza- tion of resistance to rhizomania in an ecotype of Beta vulgaris subsp. maritima.PlantPath 44:819–828 Gidner S, Lennefors BL, Nilsson NO, Bensefelt J, Johansson E, Gyllenspetz U, Kraft T (2005) QTL mapping of BNYVV resistance from the WB41 source in sugar beet. Genome 48:279–285 Grimmer M, Bean K, Asher M (2007) Mapping of five resistance genes to sugar-beet powdery mildew using AFLP and anchored SNP markers. Theor Appl Genet 115:67–75 8 Source of Useful Traits 207

Grimmer MK, Bean KMR, Luterbacher MC, Stevens M, Asher MJC (2008a) Beet mild yellowing virus resistance derived from wild and cultivated Beta germplasm. Plant Breed 127:315–318 Grimmer MK, Bean KMR, Qi A, Stevens M, Asher MJC (2008b) The action of three Beet yel- lows virus resistance QTLs depends on alleles at a novel genetic locus that controls symptom development. Plant Breed 127:391–397 Grimmer MK, Kraft T, Francis SA, Asher MJC (2008c) QTL mapping of BNYVV resistance from the WB258 source in sugar beet. Plant Breed 127:650–652 Hajjar R, Hodgkin T (2007) The use of wild relatives in crop improvement: a survey of development over the last 20 years. Euphytica 156:1–13 Hanson AD, Wyse R (1982) Biosynthesis, translocation, and accumulation of betaine in sugar beet and its progenitors in relation to salinity. Plant Physiol 70:1191–1198 Hanson LE (2006) First report of fusarium yellows of sugar beet caused by Fusarium oxysporum in Michigan. Plant Dis 90:1554 Hanson LE, Hill AL (2004) Fusarium species causing Fusarium yellows of sugarbeet. J Sugarbeet Res 41:163–178 Hanson LE, Lewellen RT (2007) Stalk Rot of sugar beet caused by Fusarium solani on the Pacific Coast. Plant Dis 91:1204 Hanson LE, Panella L (2002a) Beta PIs form the USDA-ARS NPGS evaluated for resistance to Cercospora beticola, 2001. Biological cultural tests for control of plant diseases. Am Phytopathol Soc 17:F03. doi:https://doi.org/10.1094/bc17 Hanson LE, Panella L (2002b) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to curly top virus, 2001. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 17:F04. doi:https://doi.org/10.1094/bc17 Hanson LE, Panella L (2002c) Rhizoctonia root rot resistance of Beta PIs from the USDA-ARS NPGS, 2001. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 17:F05. doi:https://doi.org/10.1094/bc17 Hanson LE, Panella L (2003a) Beta PIs from the USDA-ARS NPGS evaluated for resistance to Cercospora beticola, 2002. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 18:F015. doi:https://doi.org/10.1094/bc18 Hanson LE, Panella L (2003b) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to curly top virus, 2002. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 18:F016. doi:https://doi.org/10.1094/bc18 Hanson LE, Panella L (2003c) Rhizoctonia root-rot resistance of Beta PIs from the USDA-ARS NPGS, 2002. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 18:F014. doi:https://doi.org/10.1094/bc18 Hanson LE, Panella L (2004a) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to Beet curly top virus, 2003. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 19:FC013. doi:https://doi.org/10.1094/bc19 Hanson LE, Panella L (2004b) Rhizoctonia root-rot resistance of Beta PIsfromtheUSDA-ARS NPGS, 2003. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 19:FC012. doi:https://doi.org/10.1094/bc19 Hanson LE, Panella L (2005) Rhizoctonia root rot resistance of Beta PIs from the USDA-ARS NPGS, 2004. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 20:FC016. doi:https://doi.org/10.1094/bc20 Hanson LE, Panella L (2006) Rhizoctonia root-rot resistance of Beta PIs from the USDA-ARS, NPGS, 2005. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 21:FC011. doi:https://doi.org/10.1094/bc21 Hanson LE, Panella L (2007) Rhizoctonia root rot resistance of Beta PIs from the USDA-ARS NPGS, 2006. Plant Dis Manag Rep 1:V023. doi:https://doi.org/10.1094/pdmr01 Hanson L, de Lucchi L, Stevanato P, McGrath M, Panella L, Sella L, de Biaggi M, Concheri G (2018) Root rot symptoms in sugar beet lines caused by Fusarium oxysporum f. sp. betae.EurJ Plant Pathol 150:589. https://doi.org/10.1007/s10658-017-1302-x 208 L. W. Panella et al.

Hanson LE, Duckert T, McGrath JM (2009a) Beta PIs from the USDA-ARS NPGS evaluated for resistance to Cercospora beticola, 2008. Plant Dis Manag Rep 3:V017. https://doi.org/10.1094/ PDMR03 Hanson LE, Duckert T, Goodwill TR, McGrath JM (2010) Beta PIs from the USDA-ARS NPGS evaluated for resistance to Cercospora beticola, 2009. Plant Dis Manag Rep 4:FC005. doi:https:// doi.org/10.1094/pdmr04 Hanson LE, Duckert T, Goodwill TR, McGrath J (2011) Beta PIs from the USDA-ARS NPGS evaluated for resistance to Cercospora beticola, 2010. Plant Dis Manag Rep 5:FC056. doi:https:// doi.org/10.1094/pdmr05 Hanson LA, Hill AL, Jacobsen BJ, Panella LW (2009) Varying response of sugar beet lines to different Fusarium oxysporum f.sp. betae isolates from the United States. J Sugar Beet Res 46:11–26 Harlan JR, de Wet JMJ (1971) Toward a rational classification of cultivated plants. Taxon 24:509– 517 Harveson RM, Rush CM (1997) Genetic variation among Fusarium oxysporum isolates from sugar beet as determined by vegetative compatibility. Plant Dis 81:85–88 Harveson RM, Rush CM (2002) The influence of irrigation frequency and cultivar blends on the severity of multiple root diseases in sugar beets. Plant Dis 86:901–908 Hauser S, Stevens M, Mougel C, Smith HG, Fritsch C, Herrbach E, Lemaire O (2000) Biological, serological, and molecular variability suggest three distinct Polerovirus species infection beet or rape. Phytopathology 90:460–466 Hautekèete NC, Piquot Y, van Dijk H (2002) Life span in Beta vulgaris ssp. maritima: the effects of age at first reproduction and disturbance. J Ecol 90:508–516 Hautekèete NC, van Dijk H, Piquot Y, Teriokhin A (2009) Evolutionary optimization of life-his- tory traits in the sea beet Beta vulgaris subsp. maritima: comparing model to data. Acta Oecol 35:104–116 Hecker RJ, Ruppel EG (1979) Registration of FC 702/4, FC 702/4 (4X), FC 705, FC 706, and FC 707 sugarbeet germplasm. Crop Sci 19:935 Hecker RJ, Ruppel EG (1981) Registration of FC 708 and FC 708 CMS sugarbeet germplasm. Crop Sci 21:802 Hecker RJ, Ruppel EG (1991) Registration of Rhizoctonia root rot resistant sugarbeet germplasm FC 710. Crop Sci 31:494 Heijbroek W (1977) Partial resistance of sugarbeet to beet cyst eelworm (Heterodera schachtii Schm.). Euphytica 26:257–262 Heijbroek W, McFarlane JS, Doney DL (1977) Breeding for tolerance to beet-cyst eelworm Het- erodera schachtii Schm. in sugarbeet. Euphytica 26:557–564 Herr LJ (1996) Sugar beet diseases incited by Rhizoctonia spp. In: Sneh B (ed) Rhizoctonia species: taxonomy, molecular biology, ecology, pathology and disease control. Kluwer, Dordrecht, pp 341–350 Hill AL, Reeves PA, Larson RL, Fenwick AL, Hanson LE and Panella L (2011) Genetic variability among isolates of Fusarium oxysporum from sugar beet. Plant Pathol 60(3): 496–505. doi:https:// doi.org/10.1111/j.1365-3059.2010.02394.x Hijner JA (1951) De gevoeligheid van wilde bieten voor het bietecysteaaltje (Heterodera schachtii). Meded Inst Rat Suikerprod 21:1–13 Hjerdin A, Säll T, Nilsson NO, Bornmann CH, Halldén C (1994) Genetic Variation among wild and cultivated beets of the section Beta as revealed by RFLP analysis. J Sugar Beet Res 31:59–67 Holtschulte B (2000) Cercsopora beticola—worldwide distribution and incidence. In: Asher MJC, Holtsculhte B, Richard-Molard M, Rosso G, Steinrücken G, Beckers R (eds) Advances in sugar beet research, vol 2. Cercospora beticola Sacc. biology, agronomic influence and control measures in sugar beet. IIRB, Brussels, Belgium, pp 5–16 Jacobsen BJ, Franc GD (2009) Cercospora leaf spot. In: Harveson RM, Hanson LE, Hein GL (eds) Compendium of beet diseases and pests. American Phytopathological Society Press, St. Paul, MN, pp 7–10 8 Source of Useful Traits 209

Janssen GKW, Nihlgard M, Kraft T (2003) Mapping of resistance genes to powdery mildew (Erysiphe betae) in sugarbeet. In: Proceedings of the 1st joint IIRB-ASSBT congress held in San Antonio TX, 26th Feb–1st Mar, 2003. IIRB, Brussels, Belgium, 2-26-2003, pp 175–180 Jones PD, Lister DH, Jaggard KW, Pidgeon JD (2003) Future climate impact on the productivity of sugar beet (Beta vulgaris L.) in Europe. Clim Change 58:93–108 Jung C, Pillen K, Frese L, Fähr S, Melchinger AE (1993) Phylogenetic relationships between cultivated and wild species of the genus Beta revealed by DNA “fingerprinting”. Theor Appl Genet 86:449–457 Jung C, Herrmann RG, Eibl C, Kleine M (1994) Molecular analysis of a translocation in sugar beet carrying a gene for nematode resistance from Beta procumbens. J Sugar Beet Res 31:27–42 Kaufmann A, Koenig R, Lessemann DE (1992) Tissue printing-immunoblotting reveals an uneven distribution of beet necrotic yellow vein and beet soil-borne viruses in sugarbeets. Arch Virol 126:329–335 Kazantseva LA (1975) Evaluation of a collection of beetroot and mangel for resistance to black leg (in Russian). Byul Vses Ord Len Ord Druzhby Nar Inst Rast Imeni N I Vavilova 50:69–71 Keskin B (1964) Polymyxa betae n. sp., a parasite in the roots of Beta vulgaris torunefort, particularly during the early growth of the sugar beet. Arch Mikrobiol 19:374 Kingsnorth CS, Kingsnorth AJ, Lyons PA, Chwarszczynska DM, Asher MJC (2003) Real-time analysis of Polymyxa betae GST expression in infected sugar beet. Mol Plant Pathol 4:171–176 Koyro HW (2000) Effect of high NaCl-salinity on plant growth, leaf morphology, and ion compo- sition in leaf tissues of Beta vulgaris ssp. maritima. J Appl Bot 74:67–73 Koyro HW, Huchzermeyer B (1999) Influence of high NaCl salinity on growth, water and osmotic relations of the halophyte Beta vulgaris ssp. maritima. Development of the quick check. In: Liethe H, Moschenko M, Lohmann M, Koyro HW, Hamdy A (eds) Progress in biometerology halophyte uses in different climates I. Ecological and ecophysiological research. Bakchuys, Leinden, The Netherlands, pp 43–64 Koyro HW, Lieth H (2008) Global water crisis: the potential of cash crop halophytes to reduce the dilemma. In: Lieth H, García Sucre M, Herzog, B (eds) Mangroves and halophytes: restoration and utilisation. Tasks for vegetation science vol 34. Springer Science + Business Media, B.V., The Netherlands, pp 7–19. doi:https://doi.org/10.1007/978-1-4020-6720-4_2 Koyro HW, Daoud S, Harrouni C, Huchzermeyer B (2006) Strategies of a potential cash crop halophyte (Beta vulgaris ssp. maritima) to avoid salt injury. Trop Ecol 47:191–200 Krasochkin VT (1959) Review of the species of the genus Beta. Trudy Po Prikladnoi Botanike. Genetik i Selektsii 32:3–35 Landa BB, Navas-Cortés JA, Hervás A, Jiménez-Díaz RM (2001) Influence of temperature and inoculum density of Fusarium oxysporum f. sp. ciceris on suppression of Fusarium wilt of chick- pea by rhizosphere bacteria. Phytopathology 91:807–816. https://doi.org/10.1094/PHYTO.2001. 91.8.807 Lange W, de Bock T (1994) Pre-breeding for nematode resistance in beet. J Sugar Beet Res 31:13–26 Lange W, Brandenburg WA, de Bock TSM (1999) Taxonomy and cultonomy of beet (Beta vulgaris L.). Bot J Linn Soc 130:81–96 Lehmann W, Karl E, Schliephake E (1983) Vergleich von Methoden zur Prufung der Resistenz von Kulturpflanzen gegen Aphiden. Tag-Ber Akad Land-Wiss Berlin 216:667–677 Lewellen RT (1973) Inheritance of beet mosaic virus resistance in sugarbeet. Phytopathology 63:877–881 Lewellen RT (1988) Selection for resistance to rhizomania in sugar beet. In: Proceedings of the 5th international congress plant pathology. Kyoto, Japan, p 455 Lewellen RT (1992) Use of plant introductions to improve populations and hybrids of sugarbeet. Use of plant introductions in cultivar development, part 2. Crop Science Society of America, Madison, WI (USA), pp 117–135 Lewellen RT (1994) Registration of C790-6, C790-15, and C790-54 parental lines of sugarbeet. Crop Sci 34:319–320 210 L. W. Panella et al.

Lewellen RT (1995a) Performance of near-isolines of sugarbeet with resistance to rhizomania from different sources. In: Proceeding of the 58th IIRB congress. IIRB. IIRB, Brussels, Belgium, pp 83–92 Lewellen RT (1995b) Registration of sugarbeet germplasm lines with multiple disease resistance: C39, C39R, C39R-6, C47, C47R, C93, and C94. Crop Sci 35:596–597 Lewellen RT (1997a) Registration of 11 sugarbeet germplasm C79 lines with resistance to rhizo- mania. Crop Sci 37:1026 Lewellen RT (1997b) Registration of sugarbeet germplasm lines C78, C80, and C82. Crop Sci 37:1037 Lewellen RT (1998) Registration of C76-89-5 parental line of sugarbeet. Crop Sci 38:905 Lewellen RT (2000a) Registration of powdery mildew resistant sugarbeet germplasms CP01 and CP02. Crop Sci 40:1515 Lewellen RT (2000b) Registration of rhizomania resistant sugarbeet × Beta vulgaris subsp. mar- itima germplasms C26, C27, and C51. Crop Sci 40:1513–1515 Lewellen RT (2004a) Registration of CP03, CP04, CP05, and CP06 sugarbeet germplasms with resistance to powdery mildew, rhizomania, and other diseases. Crop Sci 44:1886–1887 Lewellen RT (2004b) Registration of CP07 and CP08 sugarbeet germplasms with resistance to powdery mildew, rhizomania, and other diseases. Crop Sci 44:2276–2277 Lewellen RT (2004c) Registration of sugar beet germplasm lines C67/2, C69/2, C78/3, and C80/2 with resistance to virus yellows and rhizomania. Crop Sci 44:358–359 Lewellen RT (2004d) Registration of sugarbeet germplasm lines C927-4, C929-62, C930-19, and C930-35 with resistance to rhizomania, virus yellows and bolting. Crop Sci 44:359–361 Lewellen RT (2006a) Registration of C931, C941, CR168, and CZ25/2 self-fertile, genetic-male- sterile facilitated, random-mated, sugarbeet germplasm populations. Crop Sci 46:1412–1413 Lewellen RT (2006b) Registration of CN12 and CN72 sugarbeet germplasm populations with resistance to cyst nematode. Crop Sci 46:1414–1415 Lewellen RT (2007) Registration of CN927-202, CN926-11-3-22, and CN921-306 sugarbeet cyst nematode resistant sugarbeet lines. J Plant Reg 1:167–169 Lewellen RT, Biancardi E (1990) Breeding and performance of rhizomania resistant sugar beet. In: 53rd congress of the international institute for sugar beet research, 14–15 Feb 1990, Brussels (Belgium), Institut International de Recherches Betteravieres, Brussels, Belgium, pp 69–87 Lewellen RT, Biancardi E (2005) Beet mosaic. In: Biancardi E, Campbell LG, Skaracis GN, de Biaggi M (eds) Genetics and breeding of sugar beet. Science, Enfield, NH, USA, pp 79–80 Lewellen RT, Pakish LM (2005) Performance of sugarbeet cyst nematode resistant cultivars and a search for sources of resistance. J Sugar Beet Res 42(1 & 2):48 Lewellen RT, Schrandt JK (2001) Inheritance of powdery mildew resistance in sugar beet derived from Beta vulgaris ssp. maritima. Plant Dis 85:627–631 Lewellen RT, Skoyen IO (1984) Beet western yellows can cause heavy losses in sugarbeet. Calif Agric 38:4–5 Lewellen RT, Whitney ED (1976) Inheritance of resistance to race C2 of Cercospora beticola in sugarbeet. Crop Sci 16:558–561 Lewellen RT, Whitney ED (1993) Registration of germplasm lines developed from composite crosses of sugar beet × Beta maritima. Crop Sci 33:882–883 Lewellen RT, Wrona AF (1997) Solarization and host-plant resistance as alternatives to soil fumi- gation to control rhizomania in sugarbeet. In: Proceedings of the 60th IIRB congress. IIRB, Brussels, Belgium, pp 189–201 Lewellen RT, Skoyen IO, Whitney ED, McFarlane JS (1982) Registration of 11 sugarbeet germ plasm lines with resistance to virus yellows. Crop Sci 22:900–901 Lewellen RT, Whitney ED, Skoyen IO (1985) Registration of C37 sugarbeet parental line. Crop Sci 25:375 Lewellen RT, Skoyen IO, Erichsen AW (1987) Breeding sugarbeet for resistance to rhizomania: evaluation of host-plant reactions and selections for and inheritance of resistance. In: Proceedings of the 50th winter congress of the IIRB. IIRB, Brussels, Belgium, pp 139–156 8 Source of Useful Traits 211

Lewellen RT, Wisler GC, Liu H-Y, Kaffka SR, Sears JL, Duffus JE (1999) Reaction of sugarbeet breeding lines and hybrids to beet chlorosis luteovirus. J Sugar Beet Res 36:76 Liu H-Y, Lewellen RT (2007) Distribution and molecular characterization of resistance-breaking isolates of Beet necrotic yellow vein virus in the United States. Plant Dis 91:847–851 Liu H-Y, Lewellen RT (2008) Suppression of resistance-breaking Beet necrotic yellow vein virus isolates by beet oak-leaf virus in sugar beet. Plant Dis 92:1043–1047 Liu H-Y, Wisler GC, Sears JL, Duffus JE (1999) Beet chlorosis virus—a new luteovirus affecting sugar beet. J Sugar Beet Res 36:69 Liu H-Y, Sears JL, Lewellen RT (2005) Occurrence of resistance-breaking Beet necrotic yellow vein virus of sugar beet. Plant Dis 89:464–468 Lowe HJB, Russell GE (1969) Inherited resistance of sugar beet to aphid colonization. Ann Appl Biol 63:337–344 Luterbacher MC, Smith JM, Asher MJC, Frese L (2000) Disease resistance in collections of Beta species. J Sugar Beet Res 37:39–47 Luterbacher MC, Asher MJC, DeAmbrogio E, Biancardi E, Stevanato P, Frese L (2004) Sources of resistance to diseases of sugar beet in related Beta germplasm: I. Foliar diseases. Euphytica 139:105–121 Luterbacher MC, Asher MJC, Beyer W, Mandolino G, Scholten OE, Frese L, Biancardi E, Stevanato P, Mechelke W, Slyvchenko O (2005) Sources of resistance to diseases of sugar beet in related Beta germplasm: II. Soil-borne diseases. Euphytica 141:49–63 Margara J, Touvin H (1955) Sur le possibilité d’obtention de types de betteraves tolerants au virus de la jaunisse. Comptes Rendus de l’Academie des Sciences de France (Paris) 41:650–655 Maxted N, Ford-Lloyd BV, Jury SL, Kell SP, Scholten MA (2006) Towards a definition of a crop wild relative. Biodivers Conserv 15:2673–2685 McFarlane JS (1971) Variety development. In: Johnson RT (ed) Advances in sugarbeet production: principles and practices. The Iowa State University Press, Ames, IA, pp 402–435 McFarlane JS (1975) Naturally occurring hybrids between sugarbeet and Beta macrocarpa in the Imperial Valley of California. J ASSBT 18:245–251 McFarlane JS, Bennett CW (1963) Occurrence of yellows resistance in the sugar beet with an appraisal of the opportunities for developing resistant varieties. J ASSBT 12:403–514 McFarlane JS, Price C (1952) A new non-bolting, curly-top-resistant sugar beet variety, U.S. 75. Proc ASSBT 7:384–386 McFarlane JS, Skoyen IO, Lewellen RT (1971) Registration of sugarbeet parental lines. Crop Sci 11:946–947 McFarlane JS, Savitsky H, Steele A (1982) Breeding for resistance to the sugarbeet nematode. J ASSBT 21:311–323 McGrath JM (2006) Registration of EL53 sugarbeet germplasm with smooth-root and moderate resistance to rhizoctonia crown and root rot. Crop Sci 46:2334–2335 McGrath JM, Derrico CA, Yu Y (1999) Genetic diversity in selected, historical US sugarbeet germplasm and Beta vulgaris ssp. maritima. Theor Appl Genet 98:968–976 McGrath JM, Elawady A, El-Khishin D, Naegele RP, Carr KM, de los Reyes B (2008) Sugar beet germination: phenotypic selection and molecular profiling to identify genes involved in abiotic stress response. Acta Hort 782:35–49 Mesken M, Lekkerkerker B (1988) Selectie op partiele resistentie tegen het bietecysteaaltje in kruisingen van suiker-en voederbieten met B. maritima. Prophyta, Bijlage Januari, pp 68–71 Mita G, Dani M, Casciari P, Pasquali A, Selva E, Minganti C, Piccardi P (1991) Assessment of the degree of genetic variation in beet based on RFLP analysis and the taxonomy of Beta. Euphytica 55:1–6 Munerati O (1932) Sull’ incrocio della barbabietola coltivata con la beta selvaggia della costa adriatica. L’Industria Saccarifera Italiana 25:303–304 Munerati O, Zapparoli TV (1915) di alcune anomalie della Beta vulgaris L. Atti Regia Accademia dei Lincei 25:1239 212 L. W. Panella et al.

Munerati O, Mezzadroli C, Zapparoli TV (1913a) Osservazioni sulla Beta maritima L. nel triennio 1910–1912. Stanz Sper Ag Ital 46:415–445 Munerati O, Mezzadroli G, Zapparoli TV (1913b) Osservazioni sulla Beta maritima L., nel triennio 1910–1912. Sta Sperimentali Agr Ital 46:415–445 Murphy AM (1946) Sugar beet and curly top history in Southern Idaho 1912–1945. Proc ASSBT 4:408–412 Mutasa ES, Ward E, Adams MJ, Collier CR, Chwarszczynska DM, Asher MJC (1993) A sensitive DNA probe for the detection of Polymyxa betae in sugar beet roots. Physiol Mol Plant Pathol 43:379–390 Mutasa ES, Chwarszczynska DM, Adams MJ, Ward E, Asher MJC (1995) Development of PCR for the detection of Polymyxa betae in sugar beet roots and its application in field studies. Physiol Mol Plant Pathol 47:303–313 Mutasa ES, Chwarszczynska DM, Asher MJC (1996) Single tube, nested PCR for the diagnosis of Polymyxa betae infection in sugar beet roots and colorimetric analysis of amplified products. Phytopathology 86:493–497 Niazi BH, Rozema J, Broekmann RA, Saline M (2000) Dynamics of growth and water relation of fodder and sea beet in response to salinity. J Agron Crop Sci 184:101–110 Niazi BH, Athar M, Saum M, Rozema J (2005) Growth and ionic relations of fodderbeet and sea- beet under saline environments. Int J Environ Sci Technol 2:113–120 Nouhi A, Amiri R, Haghnazari A, Saba J, Mesbah M (2008) Tagging of resistance gene(s) to rhizomania disease in sugar beet (Beta vulgaris L.). Afr J Biotechnol 7:430–433 Ober ES, Luterbacher MC (2002) Genotypic variation for drought tolerance in Beta vulgaris.Ann Bot 89:917–924 Ober E, Rajabi A (2010) Abiotic stress in sugar beet. Sugar Tech 12:294–298 Ober ES, Guarise M, Smith CHG, Luterbacher MC (2004a) Evaluation of drought tolerance in Beta germplasm. In: Frese L, Germeier CU, Lipman E, Maggioni L (eds) Report of a working group on Beta and world Beta network. Second joint meeting, 23–26 Oct 2002, Bologna, Italy. IIRB, Rome, Italy, pp 112–113 Ober ES, Clark CJA, Le Bloa M, Royal JKW, Pidgeon JD (2004b) Assessing the genetic resources to improve drought tolerance in sugar beet: agronomic traits of diverse genotypes under droughted and irrigated conditions. Field Crops Res 90:213–234 Ober ES, Le Bloa M, Royal A, Jaggard KW, Pidgeon JD (2005) Evaluation of physiological traits as indirect selection criteria for drought tolerance in sugar beet. Field Crops Res 91:231–249 Ogata N, Taguchi K, Kuranouchi T, Tanaka M (2000) Breeding for root rot resistant varieties. 3. Resitance of seed parents bred in NARCH. Proc Jap Soc Sugar Beet Technol 42:13–19 Oltmann W,Burba M, Bolz G (1984) Die Qualität der Zuckerrübe, Bedeutung. Beurteilungskriterien und Züchterische Massnahmen zu ihre Verbesserung, Berlin, Germany Owen FV (1942) Inheritance of cross- and self-sterility in Beta vulgaris L. J Agric Res 64:679–698 Owen FV (1945) Cytoplasmically inherited male-sterility in sugar beets. J Agric Res 71:423–440 Owen FV, Abegg FA, Murphy AM, Tolman B, Price C, Larmer FG, Carsner E (1939) Curly- top-resistant sugar-beet varieties in 1938. United States Department of Agriculture, Washington, D.C., Circular No. 513, p 10 Owen FV, Murphy AM, Ryser GK (1946) Inbred lines from curly-top-resistant varieties of sugar beet. Proc ASSBT 4:246–252 Panella L (1998a) Screening and utilizing Beta genetic resources with resistance to Rhizoctonia root rot and Cercospora leaf spot in a sugar beet breeding program. In: Frese L, Panella L, Srivastava HM, Lange W (eds) International Beta genetic resources network. A report on the 4th international Beta genetic resources workshop and world Beta network conference held at the Aegean agricultural research institute, Izmir, Turkey, 28 Feb–3 Mar 1996. International Crop Network Series No. 12. International Plant Genetic Resources Institute, Rome, pp 62–72 Panella L (1998b) Screening of Beta PIs from the USDA-ARS national plant germplasm system (NPGS) for resistance to curly top virus, 1997. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 13:149 8 Source of Useful Traits 213

Panella L (1999a) Evaluation of Beta PIs from the USDA-ARS national plant germplasm system for resistance to curly top virus, 1998. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 14:152 Panella L (1999b) Evaluation of Beta PIs from the USDA-ARS national plant germplasm system for resistance to Rhizoctonia root rot, 1998. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 14:154 Panella L (1999c) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to Cercospora leaf spot, 1998. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 14:153 Panella L (2000a) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to Cercospora leaf spot, 1999. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 15:34 Panella L (2000b) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to curly top virus, 1999. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 15:33 Panella L (2000c) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to Rhizoctonia root rot, 1999. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 15:35 Panella L (2005a) Black root. In: Biancardi E, Campbell LG, Skaracis GN, de Biaggi M (eds) Genetics and breeding of sugar beet. Science, Enfield, NH, pp 101–102 Panella L (2005b) Curly top. In: Biancardi E, Campbell LG, Skaracis GN, de Biaggi M (eds) Genetics and breeding of sugar beet. Science, Enfield, NH, pp 74–76 Panella L (2005c) Root rots. In: Biancardi E, Campbell LG, Skaracis GN, de Biaggi M (eds) Genetics and breeding of sugar beet. Science, Enfield, NH, pp 95–99 Panella L, Biancardi E (2016) Genetic resistances. In: Biancardi E, Tamada T (eds) Rhizomania. Springer Science + Bussiness Media, LLC, New York, NY, pp 195–220 Panella L, Frese L (2000) Cercospora resistance in Beta species and the development of resistant sugar beet lines. In: Asher MJC, Holtschulte B, Richard-Molard M, Rosso G, Steinrücken G, Beckers R (eds) Advances in sugar beet research, vol 2. Cercospora beticola Sacc. biology, agronomic influence and control measures in sugar beet. IIRB, Brussels, Belgium, pp 163–176 Panella L, Frese L (2003) Beta germplasm evaluation data in two databases, GRIN & IDBB. In: Proceedings from the 1st joint IIRB ASSBT congress, 26th Feb–1st Mar 2003, pp 233–241 Panella L, Hanson LE (2001a) Beta PIs from the USDA-ARS NPGS evaluated for resistance to Cercospora leaf spot, 2000. Biological and cultural tests for control of plant diseases. Am Phytopathol Soc 16:F10. doi:https://doi.org/10.1094/bc16 Panella L, Hanson LE (2001b) Evaluation of Beta PIs from the USDA-ARS NPGS for resistance to curly top virus, 2000. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 16:F9. doi:https://doi.org/10.1094/bc16 Panella L, Hanson LE (2001c) Rhizoctonia root rot resistance of Beta PIs from the USDA-ARS NPGS, 2000. Biological and cultural tests for control of plant diseases. Am Phytopathol Soc 16:F11. doi:https://doi.org/10.1094/bc16 Panella L, Lewellen RT (2005) Registration of FC301, monogerm, O-type sugarbeet population with multiple disease resistance. Crop Sci 45:2666–2667 Panella L, Lewellen RT (2007) Broadening the genetic base of sugar beet: introgression from wild relatives. Euphytica 154:382–400 Panella L, McGrath JM (2010) The history of public breeding for resistance to Cercospora leaf spot in North America. In: Lartey RT, Weiland JJ, Panella L, Crous PW, Windels CE (eds) Cercospora leaf spot of sugar beet and related species. APS, St. Paul, MN, pp 141–156 Panella L, Ruppel EG (1998) Screening of Beta PIs from the USDA-ARS national plant germplasm system for resistance to Rhizoctonia root rot, 1997. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 13:151 Panella L, Strausbaugh CA (2011a) Beet curly top resistance of USDA-ARS national plant germplasm system Plant introductions, 2009. Plant Dis Manag Rep 5:FC065. doi:https://doi. org/10.1094/pdmr05 214 L. W. Panella et al.

Panella L, Strausbaugh CA (2011b) Beet curly top resistance of USDA-ARS national plant germplasm system plant introductions, 2010. Plant Dis Manag Rep 5:FC066. doi:https://doi. org/10.1094/pdmr05 Panella L, Strausbaugh CA (2013) Beet curly top resistance in USDA-ARS plant introductions, 2012. Plant disease management reports 7:FC121. Online https://doi.org/10.1094/pdmr07 Panella L, Fenwick AL, Hill AL, McClintock M, Vagher T (2008) Rhizoctonia root rot resistance of Beta PIs from the USDA-ARS NPGS, 2007. Plant Dis Manag Rep 2:V057. doi:https://doi. org/10.1094/PDMR02 Panella L, Fenwick AL, Hill AL, Vagher T, Webb KM (2010) Rhizoctonia crown and root rot resis- tance of Beta PI from the USDA-ARS NPGS, 2009. Plant Dis Manag Rep 4:FC004. doi:https:// doi.org/10.1094/pdmr04 Panella L, Fenwick AL, Stevanato P, Eujayl I, Strausbaugh CA, Richardson KL, Wintermantel WM, Lewellen RT (2018) Registration of FC1740 and FC1741 multigerm, rhizomania-resistant sugar beet germplasm with resistance to multiple diseases. J Plant Reg 12:257–263. doi:https://doi.org/ 10.3198/jpr2017.07.0042crg Panella L, Hanson L, McGrath JM, Fenwick AL, Stevanato P, Frese L, and Lewellen RT (2015b) Registration of FC305 multigerm sugarbeet germplasm selected from a cross to a crop wild relative. J Plant Reg. 9:115–120. doi:https://doi.org/10.3198/jpr2014.08.0052crg Panella L, Lewellen RT, Webb KM (2011a) Registration of FC1018, FC1019, FC1020, and FC1022 multigerm sugarbeet pollinator germplasms with disease resistance. J Plant Reg 5:233–240 Panella L, Ruppel EG, Lioviæ I, Kristek A (1998) Screening of Beta PIs from the NPGS for resistance to Cercospora leaf spot at multiple locations, 1997. Biological and cultural test for control of plant diseases. Am Phytopathol Soc 13:150 Panella L, Vagher T, Fenwick AL, Webb KM (2011b) Rhizoctonia crown and root rot resistance of Beta PIs from the USDA-ARS national plant germplasm system, 2010. Plant Dis Manag Rep 5:FC067. doi:https://doi.org/10.1094/pdmr05 Panella L, Vagher T and Fenwick AL (2012) Rhizoctonia crown and root rot resistance of Beta PIs from the USDA-ARS, national plant germplasm system, 2011. Plant Dis Manag Rep 6:FC083. doi:https://doi.org/10.1094/pdmr06 Panella L, Vagher T, Fenwick AL (2013) Evaluation of Beta PIs from the USDA-ARS, NPGS for Rhizoctonia crown and root rot resistance, 2012. Plant Dis Manag Rep 7:FC117. doi:https://doi. org/10.1094/pdmr07 Panella L, Vagher T, Fenwick AL (2014) Evaluation of Beta PIs from the USDA-ARS, NPGS for Rhizoctonia crown and root rot resistance, 2013. Plant Dis Manag Rep 8:FC178. doi:https://doi. org/10.1094/pdmr08:fc178 Panella L, Vagher T, Fenwick AL (2015a) Rhizoctonia crown and root rot resistance evaluation of Beta PIs in Fort Collins, CO, 2014. Plant Dis Manag Rep 9:FC137. doi:https://doi.org/10.1094/ pdmr09:fc137 Panella L, Vagher T, Fenwick AL (2016) Rhizoctonia crown and root rot resistance evaluation of Beta PIs in Fort Collins, CO, 2015. Plant Dis Manag Rep 10:FC167. doi:https://doi.org/10.1094/ pdmr10 Paul H, Henken B, Bock TSM, Lange W (1992) Resistance tp Polymyxa betae in Beta species of the section Procumbentes, in hybrids with B. vulgaris and in monosomic chromosome additions of B. procumbens in B. vulgaris. Plant Breed 109:265–273 Paul H, Henken B, Scholten OE, de Bock T, Lange W (1994) Resistance to Polymoxa betae and Beet necrotic yellow vein virus in Beta species of the Section Corollinae. J Sugar Beet Res 31:1–6 Pavli OI, Stevanato P, Biancardi E, Skaracis GN (2011) Achievements and prospects in breeding for rhizomania resistance in sugar beet. Field Crops Res 122:165–172 Pegadaraju V,Nipper R, Hulke B, Qi L, Schultz Q (2013) De novo sequencing of sunflower genome for SNP discovery using RAD (Restriction site Associated DNA) approach. BMC Genom 14:556 Pidgeon JD, Werker AR, Jaggard KW, Richter GM, Lister DH, Jones PD (2001) Climatic impact on the productivity of sugar beet in Europe, 1961–1995. Agric Forest Meteorol 109:27–37 8 Source of Useful Traits 215

Pidgeon JD, Jaggard KW, Lister DH, Richter GM, Jones PD (2004) Climate impact on the produc- tivity of sugarbeet in Europe. Zuckerind 129:20–26 Pritchard FJ (1916) Some recent investigations in sugar-beet breeding. Bot Gazette 62:425–465 Rasmussen J (1932) Näjra undersokiningen over Beta maritima. Bot Notiser 33–36 Richardson KL, Mackey B, Hellier B (2019) Resistance in Beta vulgaris L. subsp. maritima (L.) Thell. to the Rz1-breaking strain of rhizomania. Genet Resour Crop Evol 66:929–939 Rietberg H, Hijner JA (1956) Die Bekampfung der Vergilbungskrankheit der Ruben in den Nieder- landen. Zucker 9:483–485 Rozema J, Zaheer SH, Niazi BH, Linders H, Broekman R (1990) Salt tolerance of Beta vulgaris L.: a comparison of the growth of seabeet and fodderbeet in response to salinity. In: Lieth H (ed) Towards the rational use of high salinity tolerant plants. Kluwer, Dordrecht, pp 193–197 Ruppel EG (1991) Pathogenicity of Fusarium spp. from diseased sugar beets and variation among sugar beet isolates of F. oxysporum. Plant Dis 75:486–489 Rush CM, Liu H-Y,Lewellen RT, Acosta-Leal R (2006) The continuing saga of rhizomania of sugar beets in the United States. Plant Dis 90:4–15 Savitsky VF (1952) Methods and results of breeding work with monogerm beets. Proc ASSBT 7:344–350 Savitsky H (1975) Hybridization between Beta vulgaris and B. procumbens and transmission of nematode (Heterodera schachtii) resistance to sugar beet. Can J Genet Cytol 17:197–209 Savitsky H (1978) Nematode (Heterodera schachtii) resistance and meiosis in diploid plants from interspecific Beta vulgaris × B. procumbens hybrids. Can J Genet Cytol 20:177–186 Schlösser LA (1957) Cercoploy—ein Fortschritt in de Cercospora-Reistenzzüchtung. Zucker 10(489–492):539 Schneider F (1937) Sur un croisement de la betterave a sucre avec Beta procumbens. Inst Belge Amelior Betterave 5:544–545 Schneider CL (1954) Methods of inoculating sugar beets with Aphanomyces cochlioides Drechs. Proc ASSBT 8:247–251 Schneider CL, Gaskill JO (1962) Tests of foreign introductions of Beta vulgaris L. for resistance to Aphanomyces cochliodes Drechs. and Rhizoctonia solani Kühn. J ASSBT 11:656–660 Scholten OE, Lange W (2000) Breeding for resistance to rhizomania in sugar beet: a review. Euphytica 112:219–231 Scholten OE, Jansen RC, Keiser LCP, de Bock TSM, Lange W (1996) Major genes for resistance to beet necrotic yellow vein virus (BNYVV) in Beta vulgaris. Euphytica 91:331–339 Scholten OE, de Bock TSM, Klein-Lankhorst R, Lange W (1999) Inheritance of resistance to beet necrotic yellow vein virus in Beta vulgaris conferred by a second gene for resistance. Theor Appl Genet 99:740–746 Shane WW, Teng PS (1992) Impact of Cercospora leaf spot on root weight, sugar yield, and purity of Beta vulgaris. Plant Dis 76:812–820 Shaw B, Thomas TH, Cooke DT (2002) Response of sugar beet (Beta vulgaris L.) to drought and nutrient deficiency stress. Plant Growth Regul 37:77–83 Shepherd TJ, Hills FJ, Hall DH (1964) Losses caused by beet mosaic virus in California grown sugar beets. J ASSBT 13:244–251 Skaracis GN, Biancardi E (2000) Breeding for cercospora resistance in sugar beet. In: Asher MJC, Holtsculhte B, Richard-Molard M, Rosso G, Steinrücken G, Beckers R (eds) Advances in sugar beet research, vol 2. Cercospora beticola Sacc. biology, agronomic influence and control measures in sugar beet. IIRB, Brussels, Belgium, pp 177–195 Skuderna AW (1925) Sugar beet breeding in the Arkansas Valley of Colorado. J Am Soc Agron 17:631–634 Smith HG, Hallsworth PB (1990) The effects of yellowing viruses on yield of sugar beet in field trials, 1985 and 1987. Ann Appl Biol 116:503–511 Smith GA, Ruppel EG (1973) Association of Cercospora leaf spot, gross sucrose, percentage sucrose, and root weight in sugarbeet. Can J Plant Sci 53:695–696 216 L. W. Panella et al.

Srivastava HM, Shahi HN, Kumar R, Bhatnagar S (2000) Genetic diversity in Beta vulgaris ssp. maritima under subtropical climate of north India. J Sugar Beet Res 37:79–87 Stevanato P, Biancardi E, Saccomani M, de Biaggi M, Mandolino G (2004) The sea beet of the Po delta. In: Frese L, Germeier CU, Lipman E, Maggioni L (eds) 2004. Report of a working group on Beta and world Beta network. Second joint meeting, 23–26 Oct 2002, Bologna, Italy. IPGRI, Rome, Italy, pp 104–107 Stevanato P, Broccanello C, Biscarini F, Del Corvo M, Sablok G, Panella L, Stella A, Concheri G (2014a) High-throughput RAD-SNP genotyping for characterization of sugar beet genotypes. Plant Mol Biol Rep 32:691–696 Stevanato P, de Biaggi M, Broccanello C, Biancardi E, Saccomani M (2015) Molecular genotyping of “Rizor” and “Holly” rhizomania resistances in sugar beet. Euphytica 204:1–5 Stevanato P, Trebbi D, Panella L, Richardson K, Broccanello C, Pakish L, Fenwick A, Saccomani M (2014b) Identification and validation of a SNP marker linked to the gene HsBvm-1 for nematode resistance in sugar beet. Plant Mol Biol Rep 33:474–479 Stevanato P,Trebbi D, Norouzi P,Broccanello C, Saccomani M (2012) Identification of SNP markers linked to the Rz1 gene in sugar beet. Int Sugar J 114:715–718 Stevens M, Hallsworth PB (2003) The effects of Beet chlorosis virus (BChV) on the yield of sugar beet. In: 1st Joint IIRB-ASSBT congress, 26 Feb–1 Mar 2003, San Antonio, TX, USA, pp 805–808 Stevens M, Hallsworth PB, Smith HG (2004) The effects of Beet mild yellowing virus and Beet chlorosis virus on the yield of UK field-grown sugar beet in 1997, 1999, and 2000. Ann Appl Biol 144:113–119 Stevens M, Patron NJ, Dolby CA, Weekes R, Hallsworth PB, Lemaire O, Smith HG (2005) Dis- tribtion and properties of geographically distinct isolates of sugar beet yellowing viruses. Plant Pathol 54:100–107 Stevens M, Liu H-Y, Lemaire O (2006) Virus diseases. In: Draycott AP (ed) Sugar beet. Blackwell, Oxford, UK, pp 256–285 Stewart D (1931) Sugar-beet yellows caused by Fusarium conglutinans var. betae. Phytopathology 21:59–70 Strausbaugh CA, Wintermantel WM, Gillen AM, Eujayl IA (2008) Curly top survey in the western United States. Phytopathology 98:1212–1217 Strausbaugh CA, Panella L (2014) Beet curly top resistance in USDA-ARS plant introduction lines, 2013. Plant Dis Manag Rep 8:FC171. doi:https://doi.org/10.1094/pdmr08:fc171 Strausbaugh CA, Panella L (2015) Beet curly top resistance in USDA-ARS plant introduction lines, 2014. Plant Dis Manag Rep 9:FC091. doi:https://doi.org/10.1094/pdmr09 Strausbaugh CA, Panella L (2016) Beet curly top resistance in USDA-ARS plant introduction lines, 2015. Plant Dis Manag Rep 10:FC056. doi:https://doi.org/10.1094/pdmr10 Strausbaugh CA, Panella L (2017) Beet curly top resistance in USDA-ARS plant introductions lines, 2016. Plant Dis Manag Rep 11:V082. (ARIS Log# 336269; Submitted Nov 30, 2016; Accepted Jan 23, 2017; Published March 14, 2017) Stump WL, Franc GD, Harveson RM, Wilson RG (2004) Strobilurin fungicide timing for Rhizoc- tonia root and crown rot suppression in sugarbeet. J Sugar Beet Res 41:17–38 Tamada T, Asher M (2016a) Ecology and Epidemiology. In: Biancardi E, Tamada T (eds) Rhizo- mania. Springer Science + Bussiness Media, LLC, New York, NY, pp 155–174 Tamada T, Asher M (2016b) The plasmodiophorid protist Polymyxa betae. In: Biancardi E, Tamada T (eds) Rhizomania. Springer Science + Bussiness Media, LLC, New York, NY, pp 135–154 Tamada T, Baba T (1973) Beet necrotic yellow vein virus from rizomania-affected sugar beet in Japan. Ann Phytopathol Soc Jpn 39:325–332 Thomas TH, Asher MJC, Smith HG, Clarke NA, Mutasa ES, Stevens M, Thompson JR (1993) The development of diagnostics for evaluating Beta germplasm. J Sugar Beet Res 30:261–266 USDA-ARS (2011a) National genetic resources program. Germplasm resources information net- work (GRIN). [Online Database] National Germplasm Resources Laboratory, Beltsville, Mary- land. http://www.ars-grin.gov/cgi-bin/npgs/html/desc.pl?49075. Accessed 28 Apr 2011 8 Source of Useful Traits 217

USDA-ARS (2011b) National genetic resources program. Germplasm resources information net- work (GRIN). [Online Database] National Germplasm Resources Laboratory, Beltsville, Mary- land. http://www.ars-grin.gov/cgi-bin/npgs/html/desc_find.pl. Accessed 06 May 2011 USDA-ARS (2011c) National genetic resources program. Germplasm resources information net- work (GRIN). [Online Database] National Germplasm Resources Laboratory, Beltsville, Mary- land. http://www.ars-grin.gov/cgi-bin/npgs/html/desc_find.pl. Accessed 02 May 2011 van Geyt JPC, Lange W, Oleo M, de Bock TSM (1990) Natural variation within the genus Beta and its possible use for breeding sugar beet: a review. Euphytica 49:57–76 Wagmann K, Hautekèete NC, Piquot Y, van Dijk H (2010) Potential for evolutionary change in the seasonal timing of germination in sea beet (Beta vulgaris ssp. maritima) mediated by seed dormancy. Genetica 138:763–773 Watson MA (1940) Studies on the transmission of sugar-beet yellows virus by the aphid, Myzus persicae (Sulz.). Proc Royal Soc London B Biol Sci 128:525–552 Weiland JJ, Lewellen RT (1999) Generation of molecular genetic markers associated with resistance to powdery mildew (Erysiphe polygoni DC) in sugarbeet (Beta vulgaris). In: Proceedings of the congress of the international society of plant-microbe interaction, 9 July 1999, p 215 Weiland JJ, Yu MH (2003) A cleaved amplified polymorphic sequence (CAPS) marker associated with root-knot nematode resistance in sugarbeet. Crop Sci 43:1814–1818 Whitney ED (1989a) Beta maritima as a source of powdery mildew resistance in sugarbeet. Plant Dis 73:487–489 Whitney ED (1989b) Identification, distribution, and testing for resistance to rhizomania in Beta maritima. Plant Dis 73:287–290 Whitney ED, Lewellen RT, Skoyen IO (1983) Reactions of sugar beet to powdery mildew: genetic variation, association among testing procedures, and results of resistance breeding. Phytopathol- ogy 73:182–185 Windels CE, Harveson RM (2009) Aphanomyces root rot. In: Harveson RM, Hanson LE, Hein GL (eds) Compendium of beet disease and pests. The American Phytopatholgical Society Press, St. Paul, MN, pp 24–27 Windels CE, Jacobsen BJ, Harveson RM (2009) Rhizoctonia root and crown rot. In: Harveson RM, Hanson LE, Hein GL (eds) Compendium of beet diseases and pests. APS, St. Paul, MN, pp 33–36 Wisler GC, Liu H-Y, Duffus JE (1994) Beet necrotic yellow vein virus and its relationship to eight sugar beet furo-like viruses from the U.S.A. Plant Dis 78:995–1001 Wisler GC, Lewellen RT, Sears JL, Wasson JW, Liu H, Wintermantel WM (2003) Interactions between Beet necrotic yellow vein virus and Beet soilborne mosaic virus in sugar beet. Plant Dis 87:1170–1175 Yu MH (1995) Identification of a Beta maritima source of resistance to root-knot nematode for sugarbeet. Crop Sci 35:1288–1290 Yu MH (1996) Registration of root-knot nematode resistant beet germplasm M66. Crop Sci 36:469 Yu MH (1997) Registration of Mi-1 root-knot nematode resistant beet germplasm line. Crop Sci 37:295 Yu MH (2001) Registration of M6-1 root-knot nematode resistant sugarbeet germplasm. Crop Sci 41:278–279 Yu MH (2002a) Registration of M1-2 beet germplasm resistant to root-knot nematode. Crop Sci 43:317–318 Yu MH (2002b) Registration of sugarbeet germplasm M1-3 resistant to root-knot nematode. Crop Sci 42:1756–1757 Yu Y (2004) Genetics of Aphanomyces disease resistance in sugarbeet (Beta vulgaris), AFLP mapping and QTL analyses. PhD Dissertation, Michigan State University Yu MH (2005) Cyst nematode. In: Biancardi E, Campbell LG, Skaracis GN, de Biaggi M (eds) Genetics and breeding of sugar beet. Science, Enfield, NH, pp 103–109 Yu MH, Lewellen RT (2004) Registration of root-knot nematode-resistant sugarbeet germplasm M6-2. Crop Sci 44:1502–1503 218 L. W. Panella et al.

YuMH, Roberts PA (2002) Selection of root-knot nematode resistant sugar beet from field plantings. Nematology 2:240 Yu MH, Heijbroek W, Pakish LM (1999) The sea beet source of resistance to multiple species of root-knot nematode. Euphytica 108:151–155 Yu MH, Pakish LM, Zhou H (2001) An isozyme marker for resistance to root-knot nematode in sugarbeet. Crop Sci 41:1051–1053 Zossimovich VP (1939) New hybrids between wild and sugar beets that are resistant to Cercospora. Selektsiya i Semenovodstvo, USSR 1939:1–16